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Retell AI MCP Server

A Model Context Protocol (MCP) server that provides tools for interacting with the Retell AI API. Build, test, deploy, and monitor AI phone agents directly through Claude or other MCP-compatible clients.

Features

This MCP server exposes 45+ tools covering all major Retell AI API endpoints:

Call Management

  • Create outbound phone calls and web calls

  • Retrieve call details including transcripts and recordings

  • List and filter calls with pagination

  • Update call metadata and data storage settings

  • Delete calls and associated data

Chat Management

  • Create chat sessions and SMS conversations

  • Send messages and receive responses

  • List and manage chat sessions

Phone Number Management

  • Purchase/register new phone numbers

  • Import existing numbers via SIP

  • Configure inbound/outbound agents per number

  • List and manage phone numbers

Agent Management

  • Create and configure voice agents

  • Create and configure chat agents

  • Publish agent versions

  • Manage agent settings (voice, language, behavior)

LLM & Conversation Flow

  • Create and manage Retell LLM configurations

  • Design conversation flows with node-based structure

  • Configure custom prompts and function calling

Knowledge Base

  • Create knowledge bases for agent context

  • Add sources (URLs, text, documents)

  • Manage knowledge base sources

Voice & Batch Operations

  • List available voices

  • Schedule batch outbound calls

  • Run automated agent tests

Account

  • Check concurrent call limits

Related MCP server: AgentPhone MCP Server

Installation

npm install
npm run build

Configuration

Environment Variable

Set your Retell AI API key as an environment variable:

export RETELL_API_KEY="your-api-key-here"

Get your API key from the Retell AI Dashboard.

Claude Code Configuration

Add the MCP server using the claude mcp add command:

claude mcp add --transport stdio retell-ai -e RETELL_API_KEY=your-api-key-here -- node /path/to/retell-ai-mcp/dist/index.js

You can also use environment variable expansion:

claude mcp add --transport stdio retell-ai -e RETELL_API_KEY=\${RETELL_API_KEY} -- node /path/to/retell-ai-mcp/dist/index.js

Option 2: Project Configuration File

Create a .mcp.json file in your project root to share with your team:

{
  "mcpServers": {
    "retell-ai": {
      "command": "node",
      "args": ["/path/to/retell-ai-mcp/dist/index.js"],
      "env": {
        "RETELL_API_KEY": "${RETELL_API_KEY}"
      }
    }
  }
}

The ${RETELL_API_KEY} syntax will expand the environment variable at runtime.

Managing the Server

# List configured MCP servers
claude mcp list

# Get details about the retell-ai server
claude mcp get retell-ai

# Remove the server
claude mcp remove retell-ai

Claude Desktop Configuration

Add this to your Claude Desktop config file:

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json Windows: %APPDATA%\Claude\claude_desktop_config.json

{
  "mcpServers": {
    "retell-ai": {
      "command": "node",
      "args": ["/path/to/retell-ai-mcp/dist/index.js"],
      "env": {
        "RETELL_API_KEY": "your-api-key-here"
      }
    }
  }
}

Available Tools

Call Tools

Tool

Description

retell_create_phone_call

Create a new outbound phone call

retell_create_web_call

Create a new web call session

retell_get_call

Retrieve details of a specific call

retell_list_calls

List and filter calls

retell_update_call

Update call metadata

retell_delete_call

Delete a call

Chat Tools

Tool

Description

retell_create_chat

Create a chat session

retell_create_sms_chat

Start an SMS conversation

retell_get_chat

Get chat details

retell_create_chat_completion

Send a message

retell_list_chats

List all chats

retell_end_chat

End a chat session

Phone Number Tools

Tool

Description

retell_create_phone_number

Purchase a phone number

retell_get_phone_number

Get phone number details

retell_list_phone_numbers

List all phone numbers

retell_update_phone_number

Update phone number settings

retell_delete_phone_number

Delete a phone number

retell_import_phone_number

Import via SIP

Voice Agent Tools

Tool

Description

retell_create_agent

Create a voice agent

retell_get_agent

Get agent details

retell_list_agents

List all agents

retell_update_agent

Update agent config

retell_delete_agent

Delete an agent

retell_publish_agent

Publish agent version

retell_get_agent_versions

Get version history

Chat Agent Tools

Tool

Description

retell_create_chat_agent

Create a chat agent

retell_get_chat_agent

Get chat agent details

retell_list_chat_agents

List chat agents

retell_update_chat_agent

Update chat agent

retell_delete_chat_agent

Delete chat agent

LLM Tools

Tool

Description

retell_create_llm

Create LLM configuration

retell_get_llm

Get LLM details

retell_list_llms

List all LLMs

retell_update_llm

Update LLM config

retell_delete_llm

Delete LLM

Conversation Flow Tools

Tool

Description

retell_create_conversation_flow

Create a flow

retell_get_conversation_flow

Get flow details

retell_list_conversation_flows

List all flows

retell_update_conversation_flow

Update a flow

retell_delete_conversation_flow

Delete a flow

Knowledge Base Tools

Tool

Description

retell_create_knowledge_base

Create knowledge base

retell_get_knowledge_base

Get KB details

retell_list_knowledge_bases

List all KBs

retell_delete_knowledge_base

Delete KB

retell_add_knowledge_base_sources

Add sources

retell_delete_knowledge_base_source

Remove source

Voice Tools

Tool

Description

retell_get_voice

Get voice details

retell_list_voices

List available voices

Batch Tools

Tool

Description

retell_create_batch_call

Schedule bulk calls

retell_create_batch_test

Run agent tests

Account Tools

Tool

Description

retell_get_concurrency

Check call limits

retell_register_phone_call

Register inbound call

Example Usage

Once configured, you can use Claude to interact with Retell AI:

List available voices:

"Show me all available voices for Retell AI"

Create an agent:

"Create a new voice agent named 'Support Bot' using the voice '11labs-Adrian' with a friendly greeting"

Make a phone call:

"Call +1234567890 from my registered number +0987654321 using the Support Bot agent"

Check call history:

"Show me all calls from the last 24 hours"

Development

# Install dependencies
npm install

# Build TypeScript
npm run build

# Watch mode for development
npm run dev

License

MIT

Available Tools

52 tools
retell_add_knowledge_base_sourcesC

Add documentation sources (URLs or text) to a knowledge base.

ParametersJSON Schema
NameRequiredDescriptionDefault
knowledge_base_idYesThe knowledge base ID
sourcesYesArray of source configurations

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden but offers minimal behavioral insight. It states the tool adds sources but doesn't disclose whether this is a mutating operation (implied), what permissions are required, how sources are processed (e.g., indexing time), rate limits, or error handling. For a tool that modifies data without annotation coverage, this is inadequate.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that front-loads the core action and resource. It wastes no words, directly stating the tool's purpose without redundancy. Every element ('Add documentation sources', 'URLs or text', 'to a knowledge base') contributes essential information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (adding sources to a knowledge base, which likely involves data processing and mutation), lack of annotations, and no output schema, the description is incomplete. It doesn't explain what happens after addition (e.g., success response, error cases, or how sources integrate with the knowledge base), leaving significant gaps for an AI agent to understand the tool's full behavior.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema fully documents both parameters (knowledge_base_id and sources array with nested properties). The description adds no additional parameter semantics beyond implying source types ('URLs or text'), which is already covered in the schema's enum and property descriptions. Baseline 3 is appropriate as the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Add') and target ('documentation sources to a knowledge base'), specifying what types of sources (URLs or text) can be added. It distinguishes from siblings like 'retell_create_knowledge_base' (creates the base itself) and 'retell_delete_knowledge_base_source' (removes sources), but doesn't explicitly mention these distinctions in the description text.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing knowledge base ID), exclusions, or comparisons with sibling tools like 'retell_create_knowledge_base' (for initial setup) or 'retell_update_agent' (which might involve knowledge bases). Usage context is implied but not stated.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_create_agentC

Create a new voice agent with specified configuration including voice, LLM engine, and behavior settings.

ParametersJSON Schema
NameRequiredDescriptionDefault
voice_idYesThe voice ID to use for the agent (use retell_list_voices to see available voices)
response_engineYesThe LLM engine configuration. Use type: 'retell-llm' with llm_id, or type: 'conversation-flow' with conversation_flow_id
agent_nameNoOptional: Display name for the agent
languageNoLanguage code (e.g., 'en-US', 'es-ES', 'multi' for multilingual)
voice_modelNoText-to-speech model to use
voice_temperatureNoVoice naturalness (0-2, default 1)
voice_speedNoSpeech rate (0.5-2, default 1)
interruption_sensitivityNoHow sensitive to user interruptions (0-1)
enable_backchannelNoEnable conversational acknowledgments like 'uh-huh', 'I see'
end_call_after_silence_msNoMilliseconds of silence before ending call
max_call_duration_msNoMaximum call duration in milliseconds
webhook_urlNoURL for receiving call event webhooks

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. While 'Create' implies a write/mutation operation, the description doesn't address critical behavioral aspects: whether this requires specific permissions, what happens on success/failure, if there are rate limits, whether the agent is immediately usable, or what the return value contains. This leaves significant gaps for a creation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that front-loads the core action ('Create a new voice agent') and mentions key configuration areas. There's no wasted verbiage, though it could potentially benefit from slightly more detail given the tool's complexity.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a creation tool with 12 parameters, no annotations, and no output schema, the description is insufficiently complete. It doesn't explain what happens after creation, whether the agent is active immediately, what permissions are needed, or what the return structure looks like. The agent needs more context about the operational implications of creating a voice agent.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema description coverage is 100%, so the schema already documents all 12 parameters thoroughly. The description adds minimal value beyond the schema by mentioning 'voice, LLM engine, and behavior settings' which loosely corresponds to some parameters, but doesn't provide additional semantic context, constraints, or relationships between parameters beyond what's in the schema descriptions.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Create a new voice agent') and specifies key configuration elements ('voice, LLM engine, and behavior settings'), making the purpose immediately understandable. However, it doesn't explicitly differentiate from sibling tools like 'retell_create_chat_agent' or 'retell_create_phone_call', which appear to create different types of agents.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives like 'retell_create_chat_agent' or 'retell_create_phone_call'. It mentions configuration elements but doesn't specify prerequisites, constraints, or appropriate contexts for creating a voice agent versus other agent types.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_create_batch_callC

Schedule bulk outbound phone calls.

ParametersJSON Schema
NameRequiredDescriptionDefault
from_numberYesThe caller's phone number
tasksYesArray of call tasks with to_number and optional metadata
nameNoName for the batch job
trigger_timestampNoUnix timestamp to start the batch (optional, starts immediately if not set)

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden but offers minimal behavioral context. 'Schedule' implies a future operation rather than immediate execution, and 'bulk' suggests multiple calls, but there's no information about permissions required, rate limits, cost implications, error handling, or what happens after scheduling (e.g., confirmation returned).

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence with zero wasted words. It's front-loaded with the core purpose and appropriately sized for what it conveys.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a tool that schedules bulk operations with no annotations and no output schema, the description is insufficient. It doesn't explain what the tool returns (e.g., batch ID, status), how errors are handled, or any system constraints. Given the complexity of batch scheduling, more context is needed.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so parameters are well-documented in the schema itself. The description adds no additional parameter semantics beyond what's in the schema (e.g., it doesn't clarify 'tasks' structure or 'trigger_timestamp' behavior). Baseline 3 is appropriate when the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose with a specific verb ('Schedule') and resource ('bulk outbound phone calls'), making it immediately understandable. It doesn't explicitly distinguish from sibling tools like 'retell_create_phone_call' or 'retell_create_batch_test', but the 'bulk' aspect provides some implicit differentiation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. With sibling tools like 'retell_create_phone_call' (single call) and 'retell_create_batch_test' (likely test batch), there's no indication of when bulk scheduling is preferred or what prerequisites might be needed.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_create_batch_testC

Run automated test scenarios against an agent.

ParametersJSON Schema
NameRequiredDescriptionDefault
agent_idYesThe agent ID to test
test_casesYesArray of test case configurations

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the tool runs automated tests but doesn't explain what 'test scenarios' entail, whether this is a read-only or mutating operation, potential side effects, rate limits, or expected output format. This leaves significant gaps for an agent to understand the tool's behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence with no wasted words. It's appropriately sized and front-loaded, clearly stating the tool's purpose without unnecessary elaboration.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity of running automated tests (which could involve mutations, side effects, or specific outputs) and the lack of annotations and output schema, the description is incomplete. It doesn't address behavioral aspects, return values, or usage context, making it inadequate for an agent to fully understand the tool's role.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, documenting both parameters ('agent_id' and 'test_cases'). The description doesn't add any meaning beyond this, such as clarifying what constitutes a test case configuration or how the agent ID is used. Baseline 3 is appropriate when the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Run automated test scenarios') and target ('against an agent'), providing a specific verb+resource combination. However, it doesn't differentiate this from sibling tools like 'retell_create_batch_call' or 'retell_create_chat_completion', which might also involve testing or batch operations.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives. The description doesn't mention prerequisites, context, or exclusions, such as whether this is for pre-deployment validation, regression testing, or how it differs from other batch or test-related operations in the sibling list.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_create_chatC

Create a new chat session with a chat agent.

ParametersJSON Schema
NameRequiredDescriptionDefault
agent_idYesThe chat agent ID to use for the session
metadataNoOptional: Custom metadata for the chat session
retell_llm_dynamic_variablesNoOptional: Dynamic variables for personalized responses

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden for behavioral disclosure. While 'Create' implies a write/mutation operation, the description doesn't address important behavioral aspects like authentication requirements, rate limits, whether the chat session is persistent, what happens on creation failure, or what the tool returns. This leaves significant gaps for an agent to understand the tool's behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, clear sentence that states the core purpose without any unnecessary words. It's appropriately sized and front-loaded with the essential information, making it highly efficient.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given that this is a creation/mutation tool with no annotations and no output schema, the description is insufficiently complete. It doesn't address what the tool returns, error conditions, or behavioral constraints. For a tool that creates resources, more contextual information is needed for an agent to use it effectively.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The description provides no parameter information, but the input schema has 100% description coverage with clear documentation for all three parameters. According to scoring rules, when schema_description_coverage is high (>80%), the baseline is 3 even with no parameter information in the description, which applies here.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Create a new chat session') and the resource ('with a chat agent'), making the purpose immediately understandable. However, it doesn't distinguish this tool from similar sibling tools like 'retell_create_chat_completion' or 'retell_create_conversation_flow', which also involve chat/communication creation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. With multiple sibling tools involving chat creation (e.g., 'retell_create_chat_completion', 'retell_create_conversation_flow'), there's no indication of what differentiates this specific chat session creation tool from those other options.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_create_chat_agentC

Create a new chat agent for text-based conversations.

ParametersJSON Schema
NameRequiredDescriptionDefault
response_engineYesThe LLM engine configuration
agent_nameNoDisplay name for the chat agent
webhook_urlNoURL for receiving chat event webhooks

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. While 'Create' implies a write/mutation operation, the description doesn't specify required permissions, whether this is idempotent, what happens on failure, or what the response contains. For a creation tool with zero annotation coverage, this leaves significant behavioral gaps.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that gets straight to the point with zero wasted words. It's appropriately sized for a creation tool and front-loads the essential information. Every word earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a creation tool with no annotations and no output schema, the description is insufficiently complete. It doesn't explain what a 'chat agent' entails, what happens after creation, or what the tool returns. The agent must rely entirely on the input schema and tool name to understand the operation's full context.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema description coverage is 100%, so the schema already documents all three parameters thoroughly. The description adds no additional parameter semantics beyond what's in the schema - it doesn't explain relationships between parameters, provide examples, or clarify edge cases. This meets the baseline for high schema coverage.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Create') and resource ('new chat agent for text-based conversations'), making the purpose immediately understandable. It distinguishes this from non-chat agent creation tools like 'retell_create_phone_call' or 'retell_create_conversation_flow', though it doesn't explicitly differentiate from the similarly named 'retell_create_agent' sibling tool.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites, when not to use it, or how it differs from similar tools like 'retell_create_agent' or 'retell_create_chat_completion'. The agent must infer usage context from the tool name alone.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_create_chat_completionC

Send a message in an existing chat session and get the agent's response.

ParametersJSON Schema
NameRequiredDescriptionDefault
chat_idYesThe chat session ID
contentYesThe message content to send

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden of behavioral disclosure. While it mentions sending a message and getting a response, it lacks critical details: whether this is a read-only or mutating operation, authentication requirements, rate limits, response format, error handling, or whether the chat session must be active. For a tool with no annotation coverage, this is inadequate.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's function. It's front-loaded with the core action and outcome, with no unnecessary words or redundancy. Every part of the sentence earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity of a chat interaction tool with no annotations and no output schema, the description is insufficient. It doesn't explain the response format, error conditions, or behavioral traits like whether the tool is idempotent or has side effects. For a tool that likely involves network calls and agent interactions, more context is needed.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, with clear documentation for both parameters (chat_id and content). The description doesn't add any semantic details beyond what the schema provides, such as format examples or constraints. With high schema coverage, the baseline score of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'Send a message in an existing chat session and get the agent's response.' It specifies the action (send message), resource (existing chat session), and outcome (get agent's response). However, it doesn't explicitly differentiate from sibling tools like 'retell_create_chat' or 'retell_end_chat', which would require a 5.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing chat session), exclusions (e.g., not for creating new chats), or compare it to related tools like 'retell_create_chat' for starting chats or 'retell_end_chat' for ending them.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_create_conversation_flowC

Create a new conversation flow for structured, node-based conversation design.

ParametersJSON Schema
NameRequiredDescriptionDefault
nameYesName for the conversation flow
nodesNoArray of node configurations defining the flow
edgesNoArray of edge configurations connecting nodes

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden but offers minimal behavioral information. It states this is a creation tool (implying mutation/write operation) but doesn't disclose permissions needed, whether the flow is immediately active, rate limits, or what happens on success/failure. The description adds some context about 'structured, node-based design' but lacks critical behavioral details for a mutation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that gets straight to the point with no wasted words. It's appropriately sized for a creation tool, though it could be slightly more informative without losing conciseness.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given this is a mutation tool with no annotations and no output schema, the description is minimally adequate but has clear gaps. It covers the basic purpose but lacks behavioral transparency, usage guidelines, and details about the created resource. The 100% schema coverage helps, but for a tool that creates complex conversation flows, more context would be beneficial.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents all three parameters (name, nodes, edges). The description adds no additional parameter semantics beyond what's in the schema—it doesn't explain what 'node configurations' or 'edge configurations' entail, their structure, or examples. Baseline 3 is appropriate when schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Create a new conversation flow') and the resource ('conversation flow'), specifying it's for 'structured, node-based conversation design'. This distinguishes it from general conversation tools but doesn't explicitly differentiate from sibling tools like retell_create_agent or retell_create_chat_agent.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives. The description doesn't mention prerequisites, when this tool is appropriate compared to other creation tools (e.g., retell_create_agent), or any exclusions. Usage context is implied but not explicit.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_create_knowledge_baseC

Create a new knowledge base for providing context to agents.

ParametersJSON Schema
NameRequiredDescriptionDefault
knowledge_base_nameYesName for the knowledge base
enable_auto_refreshNoWhether to automatically refresh sources

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden. It states the tool creates a knowledge base but doesn't disclose behavioral traits such as required permissions, whether creation is idempotent, rate limits, or what happens on failure (e.g., duplicate names). For a mutation tool with zero annotation coverage, this is a significant gap in transparency.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It is front-loaded with the core action ('Create a new knowledge base') and avoids redundancy, making it easy to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (a mutation operation with no annotations and no output schema), the description is incomplete. It lacks details on behavioral aspects (e.g., permissions, error handling) and doesn't hint at the return value or next steps (e.g., using 'retell_add_knowledge_base_sources'). For a creation tool, this leaves critical gaps for an agent.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents both parameters ('knowledge_base_name' and 'enable_auto_refresh') with clear descriptions. The description adds no additional meaning beyond what the schema provides, such as examples or constraints (e.g., name uniqueness). With high schema coverage, a baseline score of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Create a new knowledge base') and the purpose ('for providing context to agents'), which is specific and informative. It distinguishes from siblings like 'retell_list_knowledge_bases' (list) and 'retell_delete_knowledge_base' (delete), though it doesn't explicitly differentiate from 'retell_add_knowledge_base_sources' (add sources), which is a related but distinct operation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., whether an agent must exist first), timing (e.g., before adding sources), or comparisons to other tools like 'retell_list_knowledge_bases' for viewing existing ones. This leaves the agent without context for decision-making.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_create_llmC

Create a new Retell LLM configuration with custom prompts and settings.

ParametersJSON Schema
NameRequiredDescriptionDefault
modelYesThe base model (e.g., 'gpt-4o', 'claude-3.5-sonnet', 'gpt-4o-mini')
general_promptYesThe main system prompt defining the agent's behavior and personality
begin_messageNoOptional: The greeting message the agent says when call starts
general_toolsNoOptional: Array of tool configurations for function calling
inbound_dynamic_variables_webhook_urlNoOptional: Webhook URL to fetch dynamic variables for inbound calls
knowledge_base_idsNoOptional: Array of knowledge base IDs to use

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden. It states 'Create' implying a write/mutation operation, but doesn't disclose behavioral traits like required permissions, whether the creation is idempotent, rate limits, or what happens on failure. This is a significant gap for a mutation tool with zero annotation coverage.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that front-loads the core purpose. Every word earns its place with no redundancy or fluff, making it easy to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given this is a mutation tool (create) with no annotations and no output schema, the description is incomplete. It doesn't explain what the tool returns (e.g., LLM ID, success status), error conditions, or integration with other tools like retell_create_agent that might use LLM configurations.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents all parameters thoroughly. The description adds no additional meaning beyond implying 'custom prompts and settings' aligns with parameters like general_prompt and model. Baseline 3 is appropriate when schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Create') and resource ('new Retell LLM configuration'), specifying it involves 'custom prompts and settings'. It distinguishes from siblings like retell_create_agent or retell_update_llm by focusing on LLM configurations specifically, though it doesn't explicitly contrast with them.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives. With many sibling tools (e.g., retell_create_agent, retell_update_llm), the description lacks context about prerequisites, dependencies, or scenarios where creating an LLM configuration is appropriate versus other creation tools.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_create_phone_callA

Create a new outbound phone call using Retell AI. Initiates a call from a registered phone number to a target number using a configured AI agent.

ParametersJSON Schema
NameRequiredDescriptionDefault
from_numberYesThe caller's phone number in E.164 format (e.g., +14157774444). Must be a number registered with Retell.
to_numberYesThe recipient's phone number in E.164 format (e.g., +12137774445)
override_agent_idNoOptional: Specific agent ID to use for this call instead of the number's default agent
metadataNoOptional: Custom metadata to attach to the call for tracking purposes
retell_llm_dynamic_variablesNoOptional: Dynamic variables to pass to the LLM for personalized responses

TDQS

A3.5/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden but lacks critical behavioral details. It states the tool 'creates' and 'initiates' a call, implying a write/mutation operation, but doesn't disclose authentication requirements, rate limits, cost implications, error conditions, or what happens after initiation (e.g., call status tracking). For a tool that likely involves external communication and billing, this is a significant gap.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is perfectly concise with two sentences that are front-loaded and zero waste. The first sentence states the core purpose, and the second elaborates on the mechanism. Every word earns its place without redundancy or fluff.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (outbound phone calls with AI agents) and lack of annotations and output schema, the description is minimally adequate but incomplete. It covers the 'what' and basic 'how' but misses critical behavioral context like permissions, side effects, and response format. For a mutation tool with no structured safety hints, more disclosure would be beneficial.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, providing detailed parameter documentation including formats (E.164), optionality, and purposes. The description adds no additional parameter semantics beyond what's in the schema, so it meets the baseline of 3 where the schema does the heavy lifting. However, it doesn't compensate with any extra context about parameter interactions or constraints.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the specific action ('Create a new outbound phone call'), identifies the resource ('using Retell AI'), and distinguishes it from siblings by specifying it's for phone calls rather than chats, web calls, or batch calls. It explicitly mentions 'initiates a call from a registered phone number to a target number using a configured AI agent,' which provides complete operational context.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies usage context by mentioning 'registered phone number' and 'configured AI agent,' suggesting prerequisites, but doesn't explicitly state when to use this tool versus alternatives like retell_create_batch_call or retell_create_web_call. No explicit exclusions or comparative guidance is provided, leaving the agent to infer based on the 'phone call' specificity.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_create_phone_numberC

Register/purchase a new phone number for use with Retell AI agents.

ParametersJSON Schema
NameRequiredDescriptionDefault
area_codeYesThe area code for the phone number (e.g., '415' for San Francisco)
inbound_agent_idNoOptional: Agent ID to handle inbound calls to this number
outbound_agent_idNoOptional: Agent ID to use for outbound calls from this number
nicknameNoOptional: A friendly name for the phone number

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden for behavioral disclosure. It mentions 'Register/purchase' which implies a write operation, but doesn't address critical aspects like whether this incurs costs, requires specific permissions, has rate limits, or what happens on failure. The description is insufficient for a mutation tool with zero annotation coverage.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It's appropriately sized and front-loaded, with every word earning its place in conveying the essential function.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a mutation tool ('Register/purchase') with no annotations and no output schema, the description is incomplete. It doesn't address behavioral aspects like costs, permissions, or response format. While the schema covers parameters well, the overall context for using this tool safely and effectively is lacking.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents all four parameters thoroughly. The description doesn't add any parameter-specific information beyond what's in the schema. According to scoring rules, when schema coverage is high (>80%), the baseline is 3 even with no param info in the description.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Register/purchase') and resource ('new phone number for use with Retell AI agents'), providing a specific purpose. However, it doesn't differentiate from sibling tools like 'retell_import_phone_number' or 'retell_update_phone_number', which would require explicit comparison to achieve a score of 5.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives like 'retell_import_phone_number' or 'retell_update_phone_number'. It lacks context about prerequisites, costs, or limitations, offering only a basic functional statement without usage boundaries.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_create_sms_chatC

Start an outbound SMS conversation using a specified chat agent.

ParametersJSON Schema
NameRequiredDescriptionDefault
from_numberYesThe sender's phone number in E.164 format
to_numberYesThe recipient's phone number in E.164 format
agent_idYesThe chat agent ID to handle the conversation
metadataNoOptional: Custom metadata for the SMS chat

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the tool initiates an SMS conversation but fails to describe key behaviors: whether this is a one-time message or starts an ongoing chat, what permissions or authentication are required, potential rate limits, or the expected outcome (e.g., does it return a chat ID?). This leaves significant gaps for an agent to understand how the tool operates.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without any redundant or extraneous information. It is front-loaded with the core action, making it easy to parse quickly, and every word contributes to understanding the tool's function.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity of initiating an SMS conversation (a write operation with no output schema and no annotations), the description is incomplete. It lacks details on behavioral aspects like authentication needs, error handling, or what the tool returns, which are crucial for an agent to use it effectively. The high schema coverage helps with parameters, but overall context is insufficient for a mutation tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, clearly documenting all parameters (e.g., phone numbers in E.164 format, agent ID, optional metadata). The description adds no additional semantic context beyond what the schema provides, such as examples or constraints on metadata. Given the high schema coverage, a baseline score of 3 is appropriate, as the schema handles the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Start an outbound SMS conversation') and the resource ('using a specified chat agent'), making the purpose specific and understandable. However, it doesn't explicitly differentiate from sibling tools like 'retell_create_phone_call' or 'retell_create_chat', which involve different communication channels or contexts, leaving some ambiguity about when to choose SMS over other options.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives, such as 'retell_create_phone_call' for voice calls or 'retell_create_chat' for non-SMS chats. It also lacks information on prerequisites, like whether the agent must be configured for SMS, leaving the agent to infer usage from context alone.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_create_web_callB

Create a new web call session. Returns a call ID and access token for establishing a WebRTC connection.

ParametersJSON Schema
NameRequiredDescriptionDefault
agent_idYesThe agent ID to use for the web call
metadataNoOptional: Custom metadata to attach to the call
retell_llm_dynamic_variablesNoOptional: Dynamic variables to pass to the LLM

TDQS

B3.1/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool creates a session and returns a call ID and access token for WebRTC, which implies a write operation and output format. However, it lacks critical details: whether this requires authentication, rate limits, side effects (e.g., if it consumes resources), error conditions, or how the access token should be used. For a creation tool with zero annotation coverage, this is a significant gap.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two sentences with zero waste: the first states the purpose, and the second specifies the return values. It's front-loaded with the core action and efficiently conveys essential information without redundancy or fluff, making it easy for an agent to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (a creation operation with WebRTC integration) and lack of annotations and output schema, the description is minimally adequate. It covers the basic purpose and return values but misses behavioral context like authentication needs, error handling, or usage examples. Without an output schema, it should ideally describe the return structure more fully, but it does state the key outputs (call ID and access token), which provides some completeness.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema fully documents all three parameters (agent_id, metadata, retell_llm_dynamic_variables) with descriptions. The description adds no additional parameter semantics beyond what the schema provides, such as examples or constraints. With high schema coverage, the baseline score of 3 is appropriate, as the description doesn't compensate but doesn't need to.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Create a new web call session') and the resource ('web call'), which is specific and unambiguous. It distinguishes from siblings like 'retell_create_phone_call' by specifying 'web call' rather than phone-based alternatives. However, it doesn't explicitly differentiate from other creation tools like 'retell_create_chat' or 'retell_create_conversation_flow', which slightly limits sibling distinction.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing agent), exclusions, or comparisons to sibling tools like 'retell_create_phone_call' or 'retell_create_chat'. The agent must infer usage from the tool name alone, which is insufficient for optimal selection.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_delete_agentC

Delete a voice agent from your account.

ParametersJSON Schema
NameRequiredDescriptionDefault
agent_idYesThe agent ID to delete

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden. 'Delete' implies a destructive mutation, but the description doesn't disclose critical behavioral traits: whether deletion is permanent or reversible, what permissions are required, if there are rate limits, or what happens to associated resources. This leaves significant gaps for a destructive operation.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that front-loads the core action and resource. There is zero wasted language, making it immediately understandable without unnecessary elaboration.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a destructive tool with no annotations and no output schema, the description is incomplete. It doesn't address the mutation's impact (e.g., permanence, side effects), error conditions, or return values, leaving the agent with insufficient context to use it safely and effectively.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% with the single parameter 'agent_id' well-documented in the schema. The description adds no additional parameter semantics beyond what's already in the structured schema, so it meets the baseline for high coverage without adding value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Delete') and resource ('a voice agent from your account'), making the purpose immediately understandable. However, it doesn't differentiate this from other delete operations like retell_delete_chat_agent or retell_delete_phone_number, which would require specifying this is specifically for voice agents.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., agent must exist), exclusions (e.g., cannot delete active agents), or relationships with sibling tools like retell_list_agents or retell_get_agent for verification.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_delete_callB

Delete a call and all associated data including recordings and transcripts.

ParametersJSON Schema
NameRequiredDescriptionDefault
call_idYesThe unique identifier of the call to delete

TDQS

B3.2/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the tool deletes a call and associated data, indicating a destructive operation, but lacks details on permissions required, whether deletion is reversible, error handling (e.g., if the call_id is invalid), or side effects (e.g., impact on linked resources). This is a significant gap for a mutation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that front-loads the key action ('Delete') and scope. Every word earns its place by specifying the resource and what gets removed (recordings and transcripts), with no redundant or vague phrasing.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a destructive tool with no annotations and no output schema, the description is incomplete. It lacks critical context such as confirmation of irreversibility, required permissions, error responses, or what happens to related entities. The high schema coverage doesn't compensate for these behavioral gaps, making it inadequate for safe agent use.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with the single parameter 'call_id' documented as 'The unique identifier of the call to delete'. The description adds no additional parameter semantics beyond what the schema provides, such as format examples or constraints. Baseline 3 is appropriate when the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Delete') and resource ('a call and all associated data including recordings and transcripts'), distinguishing it from siblings like retell_end_chat (which might terminate a chat without deletion) or retell_update_call (which modifies rather than removes). It specifies the comprehensive scope of deletion beyond just the call record.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives (e.g., retell_end_chat for stopping a chat without deletion) or prerequisites (e.g., whether the call must be in a certain state). The description implies it's for permanent removal, but lacks explicit conditions or warnings about irreversible actions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_delete_chat_agentC

Delete a chat agent.

ParametersJSON Schema
NameRequiredDescriptionDefault
agent_idYesThe chat agent ID to delete

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden. 'Delete' implies a destructive mutation, but the description doesn't disclose whether this is permanent, reversible, requires specific permissions, affects associated resources, or has confirmation requirements. For a destructive operation with zero annotation coverage, this is a significant gap in behavioral context.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that states the core purpose without unnecessary words. It's appropriately sized for a simple deletion operation and front-loads the essential information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a destructive deletion tool with no annotations and no output schema, the description is incomplete. It doesn't address critical behavioral aspects like permanence, side effects, or response format, leaving significant gaps for an AI agent to understand the tool's full implications.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with the single parameter 'agent_id' clearly documented in the schema. The description adds no additional parameter information beyond what the schema provides, so it meets the baseline for high schema coverage without compensating value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Delete') and resource ('a chat agent'), making the purpose immediately understandable. It distinguishes from siblings like 'retell_delete_agent' by specifying 'chat agent' rather than generic 'agent'. However, it doesn't explicitly differentiate from 'retell_end_chat' or 'retell_delete_call', which could involve chat-related deletions.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. With siblings like 'retell_delete_agent', 'retell_end_chat', and 'retell_delete_call', there's no indication of which deletion operation applies to chat agents specifically versus other agent types or chat sessions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_delete_conversation_flowC

Delete a conversation flow.

ParametersJSON Schema
NameRequiredDescriptionDefault
conversation_flow_idYesThe conversation flow ID to delete

TDQS

C2.7/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden for behavioral disclosure. It states the tool deletes a conversation flow, implying a destructive operation, but doesn't specify if deletion is permanent, requires specific permissions, has side effects (e.g., affecting related calls or chats), or provides confirmation. This leaves significant behavioral gaps for a mutation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence with zero waste. It's appropriately sized for a simple deletion tool and front-loads the core action, making it easy to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's destructive nature, lack of annotations, and no output schema, the description is incomplete. It doesn't address critical context like deletion consequences, error handling, or return values, which are essential for safe agent operation. Sibling tools provide more context (e.g., retell_delete_call has similar gaps), but this doesn't compensate for the missing information.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, with the parameter 'conversation_flow_id' clearly documented. The description doesn't add any meaning beyond the schema (e.g., format examples or sourcing guidance), so it meets the baseline of 3 where the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose3/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states the action ('Delete') and target resource ('a conversation flow'), which provides basic purpose clarity. However, it doesn't specify what a conversation flow is or how it differs from other conversation-related resources like calls or chats, making it somewhat vague compared to sibling tools like retell_delete_call or retell_delete_chat_agent.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided about when to use this tool versus alternatives. The description doesn't mention prerequisites (e.g., needing an existing conversation flow), exclusions, or relationships to sibling tools like retell_list_conversation_flows or retell_update_conversation_flow, leaving the agent with no usage context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_delete_knowledge_baseC

Delete a knowledge base.

ParametersJSON Schema
NameRequiredDescriptionDefault
knowledge_base_idYesThe knowledge base ID to delete

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden but only states the action without behavioral details. It doesn't disclose if deletion is permanent, requires specific permissions, affects associated resources, or has rate limits. 'Delete' implies a destructive operation, but the description lacks crucial context for safe use.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, direct sentence with zero wasted words. It's front-loaded with the core action and resource, making it highly efficient and easy to parse at a glance.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a destructive tool with no annotations and no output schema, the description is incomplete. It doesn't cover behavioral risks, success/failure responses, or usage context. Given the complexity of deletion operations and lack of structured safety hints, more guidance is needed for reliable agent use.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with the single parameter 'knowledge_base_id' fully documented in the schema. The description adds no additional parameter semantics beyond what's in the schema, so it meets the baseline score of 3 for high schema coverage without extra value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Delete') and resource ('a knowledge base'), making the purpose immediately understandable. However, it doesn't differentiate this tool from sibling deletion tools like 'retell_delete_agent' or 'retell_delete_knowledge_base_source' beyond the resource name, which prevents a perfect score.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. There's no mention of prerequisites (e.g., whether the knowledge base must be empty), consequences, or relationships with sibling tools like 'retell_delete_knowledge_base_source' or 'retell_list_knowledge_bases' for verification.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_delete_knowledge_base_sourceC

Remove a source from a knowledge base.

ParametersJSON Schema
NameRequiredDescriptionDefault
knowledge_base_idYesThe knowledge base ID
source_idYesThe source ID to delete

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool removes a source, implying a destructive mutation, but does not address critical aspects like permissions required, whether the deletion is permanent or reversible, error handling (e.g., if the source doesn't exist), or rate limits. This leaves significant gaps in understanding the tool's behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, direct sentence that efficiently conveys the core action without unnecessary words. It is front-loaded with the essential information ('Remove a source from a knowledge base'), making it highly concise and well-structured for quick understanding.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity of a destructive operation with no annotations and no output schema, the description is insufficient. It lacks details on behavioral traits (e.g., permanence, errors), output format, or integration with sibling tools. For a mutation tool with zero annotation coverage, more context is needed to ensure safe and correct usage.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, with clear parameter definitions ('knowledge_base_id' and 'source_id'), so the schema already provides full parameter semantics. The description does not add any additional meaning beyond what the schema specifies, such as format examples or contextual usage of the IDs, which aligns with the baseline score of 3 when schema coverage is high.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Remove') and target ('a source from a knowledge base'), which is specific and unambiguous. However, it does not explicitly differentiate from sibling tools like 'retell_delete_knowledge_base' (which deletes the entire knowledge base) or 'retell_add_knowledge_base_sources' (which adds sources), though the distinction is implied by the tool name.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives, such as when to delete a source versus the entire knowledge base, or prerequisites like ensuring the source exists. It lacks explicit context or exclusions, leaving usage unclear beyond the basic action.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_delete_llmC

Delete a Retell LLM configuration.

ParametersJSON Schema
NameRequiredDescriptionDefault
llm_idYesThe LLM configuration ID to delete

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden. 'Delete' implies a destructive mutation, but the description doesn't disclose whether deletion is permanent, requires specific permissions, has confirmation steps, or what happens to associated resources. This is a significant gap for a destructive operation.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that states the core purpose without any fluff or redundant information. It's appropriately sized for a simple delete operation with one parameter.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a destructive mutation tool with no annotations and no output schema, the description is inadequate. It doesn't explain behavioral implications (permanence, side effects), success/failure responses, or usage context relative to sibling tools. The agent lacks critical information to use this tool safely and correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with the single parameter 'llm_id' fully documented in the schema. The description adds no additional parameter context beyond what's already in the structured schema, meeting the baseline expectation when schema coverage is complete.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb ('Delete') and resource ('a Retell LLM configuration'), making the purpose immediately understandable. It doesn't explicitly differentiate from sibling tools like 'retell_delete_agent' or 'retell_delete_knowledge_base', but the resource specificity (LLM configuration) provides implicit differentiation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives, prerequisites, or consequences. With multiple delete operations available (agent, call, knowledge base, etc.), the agent receives no help in selecting the correct deletion tool for an LLM configuration specifically.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_delete_phone_numberC

Delete/release a phone number from your account.

ParametersJSON Schema
NameRequiredDescriptionDefault
phone_numberYesThe phone number in E.164 format to delete

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden for behavioral disclosure. It states the action is 'Delete/release' but doesn't clarify if this is reversible, requires specific permissions, affects ongoing calls, or has rate limits. The dual terms 'Delete/release' add ambiguity about the exact behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It's appropriately sized for a simple deletion operation and front-loaded with the core action.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a destructive operation with no annotations and no output schema, the description is incomplete. It doesn't address critical context like whether deletion is permanent, what happens to associated resources, error conditions, or response format, leaving significant gaps for agent decision-making.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% with one parameter fully documented in the schema. The description adds no additional parameter semantics beyond what's in the schema (e.g., format details, validation rules, or examples), so it meets the baseline for high schema coverage without adding value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Delete/release') and resource ('a phone number from your account'), making the purpose immediately understandable. However, it doesn't differentiate this tool from sibling deletion tools like 'retell_delete_agent' or 'retell_delete_call' beyond the resource type, which prevents a perfect score.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing phone number), consequences of deletion, or when to choose this over other deletion tools like 'retell_delete_phone_number' versus 'retell_import_phone_number' for managing numbers.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_end_chatC

End an active chat session.

ParametersJSON Schema
NameRequiredDescriptionDefault
chat_idYesThe chat session ID to end

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden but offers minimal behavioral insight. It states the action is to 'end' a session, implying a destructive operation, but doesn't clarify if this is reversible, what happens to chat data, or if specific permissions are required. This leaves significant gaps for a mutation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, direct sentence with zero wasted words. It's front-loaded with the core action and resource, making it highly efficient and easy to parse.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a destructive operation with no annotations and no output schema, the description is inadequate. It lacks critical context such as what 'ending' entails (e.g., data deletion, session termination), error conditions, or response format, leaving the agent under-informed about tool behavior.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema description coverage is 100%, with the single parameter 'chat_id' well-documented in the schema. The description adds no additional parameter context beyond what the schema already provides, so it meets the baseline score of 3 for high schema coverage.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('End') and resource ('an active chat session'), making the purpose immediately understandable. However, it doesn't differentiate this tool from sibling tools like 'retell_delete_chat' or 'retell_delete_call', which might have overlapping functionality.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives like 'retell_delete_chat' or 'retell_update_call' for ending chats. There's no mention of prerequisites (e.g., chat must be active) or consequences, leaving the agent without context for proper tool selection.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_get_agentC

Retrieve the configuration and details of a specific voice agent.

ParametersJSON Schema
NameRequiredDescriptionDefault
agent_idYesThe unique identifier of the agent

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden but only states it 'retrieves' details without disclosing behavioral traits. It doesn't mention whether this is a read-only operation, requires authentication, has rate limits, returns structured data, or handles errors. For a tool with zero annotation coverage, this leaves significant gaps in understanding its behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It's front-loaded with the core action ('retrieve') and resource, making it easy to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the lack of annotations and output schema, the description is incomplete for a retrieval tool. It doesn't explain what 'configuration and details' includes, the return format, or error handling. While the schema covers the input well, the overall context for proper tool invocation remains insufficient.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The description adds no parameter semantics beyond what the schema provides, which has 100% coverage with a clear description for 'agent_id'. The baseline score of 3 is appropriate since the schema fully documents the single required parameter, and the description doesn't need to compensate for gaps.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb 'retrieve' and the resource 'configuration and details of a specific voice agent', making the purpose unambiguous. However, it doesn't explicitly differentiate from sibling tools like 'retell_get_agent_versions' or 'retell_list_agents', which also retrieve agent information but with different scopes.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives like 'retell_list_agents' (for listing multiple agents) or 'retell_get_agent_versions' (for version-specific details). It mentions 'specific voice agent' but doesn't clarify prerequisites or exclusions, leaving the agent to infer usage context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_get_agent_versionsB

Retrieve the version history of an agent.

ParametersJSON Schema
NameRequiredDescriptionDefault
agent_idYesThe agent ID to get versions for

TDQS

B3.1/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden for behavioral disclosure. It states the tool retrieves data, implying it's a read-only operation, but doesn't clarify aspects like authentication requirements, rate limits, pagination for multiple versions, error conditions, or what 'version history' entails (e.g., timestamps, changes). For a retrieval tool with zero annotation coverage, this leaves significant gaps in understanding its behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It is front-loaded with the core action and resource, making it easy to parse quickly. There is no wasted language or redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple retrieval tool with one parameter and no output schema, the description is minimally adequate. It covers the basic purpose but lacks details on behavioral aspects (e.g., response format, error handling) and usage context. Without annotations or output schema, the description should provide more completeness, but it meets a bare minimum for understanding what the tool does.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, with the single parameter 'agent_id' clearly documented. The description adds no additional parameter semantics beyond what the schema provides, such as format examples or constraints. Given the high schema coverage, the baseline score of 3 is appropriate, as the schema adequately handles parameter documentation.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('retrieve') and resource ('version history of an agent'), making the purpose immediately understandable. It distinguishes this tool from other retrieval tools like 'retell_get_agent' by specifying it fetches version history rather than current agent details. However, it doesn't explicitly differentiate from all sibling tools beyond this implicit scope.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing agent), compare it to similar tools like 'retell_get_agent' or 'retell_list_agents', or specify use cases for accessing version history versus current state. Usage is implied but not articulated.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_get_callB

Retrieve details of a specific call including transcript, recording URL, duration, and analysis.

ParametersJSON Schema
NameRequiredDescriptionDefault
call_idYesThe unique identifier of the call to retrieve

TDQS

B3.1/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden for behavioral disclosure. It states this is a retrieval operation but doesn't mention authentication requirements, rate limits, error conditions, or what happens if the call_id doesn't exist. It lists data elements returned but doesn't describe format, completeness, or access permissions for recordings.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that front-loads the core purpose ('retrieve details of a specific call') followed by specific data elements. Every word contributes value with zero waste or redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a read operation with 100% schema coverage and no output schema, the description adequately covers what data is retrieved. However, without annotations and with behavioral gaps (no error handling, authentication, or format details), it's minimally complete but leaves important operational context unspecified.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% with the single parameter 'call_id' well-documented in the schema. The description doesn't add any parameter-specific information beyond what the schema provides (e.g., format examples, where to find call IDs, or validation rules), so it meets the baseline for high schema coverage.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'Retrieve details of a specific call' with specific data elements listed (transcript, recording URL, duration, analysis). It uses a specific verb ('retrieve') and resource ('call'), but doesn't explicitly distinguish it from sibling tools like 'retell_get_agent' or 'retell_get_chat' which retrieve different resources.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention sibling tools like 'retell_list_calls' (for listing multiple calls) or 'retell_update_call' (for modifying calls), nor does it specify prerequisites or appropriate contexts for retrieval.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_get_chatC

Retrieve details of a specific chat session.

ParametersJSON Schema
NameRequiredDescriptionDefault
chat_idYesThe unique identifier of the chat to retrieve

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden but only states it retrieves details without disclosing behavioral traits such as authentication needs, rate limits, error handling, or what 'details' include. It's vague and insufficient for a read operation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It's appropriately sized and front-loaded, with zero waste.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given no annotations and no output schema, the description is incomplete. It doesn't explain what 'details' are returned, potential errors, or behavioral context, leaving significant gaps for a tool that retrieves data.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema fully documents the 'chat_id' parameter. The description adds no meaning beyond this, as it doesn't explain parameter context or usage. Baseline 3 is appropriate when schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb 'retrieve' and resource 'details of a specific chat session', making the purpose understandable. However, it doesn't differentiate from sibling tools like 'retell_get_call' or 'retell_get_chat_agent' that also retrieve specific resources, missing full sibling distinction.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives like 'retell_list_chats' for listing chats or other 'retell_get_*' tools for different resources. It lacks explicit context or exclusions, offering minimal usage direction.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_get_chat_agentB

Retrieve details of a specific chat agent.

ParametersJSON Schema
NameRequiredDescriptionDefault
agent_idYesThe chat agent ID

TDQS

B3.1/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden for behavioral disclosure but offers minimal information. It doesn't indicate whether this is a read-only operation, what authentication is required, whether rate limits apply, what format the returned details follow, or if there are any side effects. For a retrieval tool with zero annotation coverage, this represents a significant transparency gap.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is perfectly concise at just one sentence that directly states the tool's purpose. There's zero wasted language, no redundancy, and the information is front-loaded effectively. Every word earns its place in this minimal but complete statement of function.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple retrieval tool with one parameter and no output schema, the description provides the basic purpose but lacks important context. Without annotations or output schema, the agent doesn't know what details are returned, in what format, or under what conditions. The description is adequate for the simplest case but doesn't prepare the agent for potential complexities or edge cases.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, with the single parameter 'agent_id' clearly documented as 'The chat agent ID'. The description doesn't add any meaningful semantic information beyond what the schema already provides, such as format examples, validation rules, or relationship to other identifiers. With complete schema coverage, the baseline score of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb ('retrieve details') and resource ('specific chat agent'), making the purpose immediately understandable. However, it doesn't differentiate this tool from similar sibling tools like 'retell_get_agent' or 'retell_list_chat_agents', which would require more specificity about what distinguishes this particular retrieval operation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance about when to use this tool versus alternatives. With sibling tools like 'retell_get_agent', 'retell_list_chat_agents', and 'retell_get_chat' available, the agent receives no indication about whether this is for single-agent lookup, bulk retrieval, or chat-specific agent details. The description lacks any contextual usage information.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_get_concurrencyA

Check the current concurrent call limits and usage for your account.

ParametersJSON Schema
NameRequiredDescriptionDefault

No parameters

TDQS

A3.5/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden. It states the tool checks limits and usage, implying a read-only operation, but doesn't disclose behavioral traits such as authentication requirements, rate limits, response format, or whether it provides real-time or cached data.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that front-loads the core purpose without any wasted words. It directly communicates what the tool does in a clear and structured manner.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (simple read operation with no parameters) and lack of annotations or output schema, the description is minimally adequate. It states the purpose but lacks details on behavior, response format, or error handling, leaving gaps for an AI agent to infer.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool has 0 parameters, and schema description coverage is 100%, so no parameter documentation is needed. The description appropriately omits parameter details, earning a baseline score of 4 for not adding unnecessary information.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the specific action ('Check') and resource ('current concurrent call limits and usage for your account'), distinguishing it from sibling tools that focus on creating, deleting, or updating various entities rather than retrieving account-level usage metrics.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No explicit guidance on when to use this tool versus alternatives is provided. The description implies usage for monitoring account limits, but it doesn't specify prerequisites, frequency, or contrast with other tools like retell_list_calls or retell_get_call for related information.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_get_conversation_flowC

Retrieve a conversation flow configuration.

ParametersJSON Schema
NameRequiredDescriptionDefault
conversation_flow_idYesThe conversation flow ID

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden. It states 'Retrieve' which implies a read operation, but doesn't disclose behavioral traits such as authentication requirements, rate limits, error conditions, or what happens if the ID is invalid. For a tool with zero annotation coverage, this leaves significant gaps.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence with zero waste. It's front-loaded with the core purpose and appropriately sized for a simple retrieval tool, making it easy to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the lack of annotations and output schema, the description is incomplete. It doesn't explain what a 'conversation flow configuration' entails, the return format, or error handling. For a tool with no structured data beyond the input schema, more context is needed to guide effective use.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with the parameter 'conversation_flow_id' fully documented in the schema. The description doesn't add any meaning beyond what the schema provides (e.g., format examples or context about where to find the ID), so it meets the baseline of 3 when the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Retrieve') and resource ('conversation flow configuration'), providing a specific verb+resource combination. However, it doesn't differentiate this tool from similar retrieval tools like 'retell_get_agent' or 'retell_get_knowledge_base' that follow the same pattern, missing sibling differentiation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives. While the name implies it's for retrieving a specific conversation flow, there's no mention of prerequisites (e.g., needing a valid ID) or when to choose this over listing tools like 'retell_list_conversation_flows'.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_get_knowledge_baseC

Retrieve a knowledge base configuration.

ParametersJSON Schema
NameRequiredDescriptionDefault
knowledge_base_idYesThe knowledge base ID

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. It states 'Retrieve' but doesn't clarify if this is a read-only operation, what permissions are needed, how errors are handled, or what the response format looks like. This leaves significant gaps in understanding the tool's behavior beyond the basic action.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without any wasted words. It's front-loaded and appropriately sized for a simple retrieval operation, making it easy to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the lack of annotations and output schema, the description is incomplete for a retrieval tool. It doesn't explain what 'configuration' entails, the return format, or any behavioral aspects like error handling. For a tool with no structured support, more context is needed to be fully helpful.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, with the parameter 'knowledge_base_id' clearly documented. The description doesn't add any extra meaning beyond the schema, such as format examples or constraints, so it meets the baseline for high schema coverage without compensating value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Retrieve') and resource ('knowledge base configuration'), which is specific and unambiguous. However, it doesn't explicitly differentiate from sibling tools like 'retell_list_knowledge_bases' or 'retell_get_agent', which might also retrieve knowledge-related information, leaving some room for improvement in sibling distinction.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention when to choose this over 'retell_list_knowledge_bases' for listing all bases or 'retell_get_agent' for agent-specific knowledge, nor does it specify prerequisites or context for usage.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_get_llmC

Retrieve a Retell LLM configuration.

ParametersJSON Schema
NameRequiredDescriptionDefault
llm_idYesThe LLM configuration ID

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden but only states the basic action without behavioral details. It doesn't disclose whether this is a read-only operation, what permissions are required, error handling (e.g., invalid IDs), or response format. For a retrieval tool with zero annotation coverage, this is a significant gap in transparency.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that front-loads the core purpose without unnecessary words. It avoids redundancy and wastes no space, making it easy for an agent to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the lack of annotations and output schema, the description is incomplete for a retrieval tool. It doesn't explain what data is returned (e.g., configuration details, status) or behavioral aspects like error cases. With 100% schema coverage, the input is well-documented, but overall context remains insufficient for confident tool invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, with 'llm_id' clearly documented as 'The LLM configuration ID'. The description adds no additional parameter semantics beyond what the schema provides, such as format examples or constraints. This meets the baseline score of 3 when schema coverage is high.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Retrieve') and resource ('Retell LLM configuration'), making the purpose immediately understandable. It distinguishes itself from sibling tools like 'retell_create_llm' and 'retell_update_llm' by focusing on retrieval rather than creation or modification. However, it doesn't specify the scope (e.g., all fields or specific metadata), which prevents a perfect score.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives. While the description implies it's for retrieving existing configurations, it doesn't mention prerequisites (e.g., needing a valid LLM ID) or contrast with similar tools like 'retell_list_llms' for listing all configurations. This leaves the agent without explicit usage context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_get_phone_numberC

Retrieve details of a specific phone number.

ParametersJSON Schema
NameRequiredDescriptionDefault
phone_numberYesThe phone number in E.164 format to retrieve

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. It states 'retrieve details' which implies a read-only operation, but doesn't clarify authentication needs, rate limits, error handling, or what 'details' encompass (e.g., configuration, usage stats). This leaves significant gaps for a tool that likely interacts with sensitive resources.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that front-loads the core purpose without unnecessary words. It avoids redundancy and wastes no space, making it easy to parse quickly while conveying the essential action.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the lack of annotations and output schema, the description is incomplete for a tool that retrieves resource details. It doesn't explain what 'details' include (e.g., metadata, settings, status), potential response formats, or error conditions, leaving the agent under-informed about the tool's behavior and outputs.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, clearly documenting the single required parameter 'phone_number' with its format (E.164). The description adds no additional parameter semantics beyond what the schema provides, so it meets the baseline for high schema coverage without compensating value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('retrieve details') and resource ('specific phone number'), making the purpose immediately understandable. However, it doesn't differentiate from sibling tools like 'retell_get_agent' or 'retell_get_call' beyond the resource type, nor does it specify what 'details' include, which prevents a perfect score.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing phone number), compare to 'retell_list_phone_numbers' for browsing, or specify use cases like checking configuration or status, leaving the agent with minimal context for selection.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_get_voiceC

Retrieve details of a specific voice.

ParametersJSON Schema
NameRequiredDescriptionDefault
voice_idYesThe voice ID to retrieve

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden but only states the basic action without behavioral details. It doesn't disclose if this is a read-only operation, requires authentication, has rate limits, or what the response format might be, which are critical for a retrieval tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without any fluff or redundancy. It is appropriately sized and front-loaded, making it easy to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given no annotations and no output schema, the description is incomplete for a retrieval tool. It lacks details on behavioral traits, response format, and usage context, which are essential for an agent to understand how to invoke and interpret results effectively.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with the single parameter 'voice_id' well-documented in the schema. The description adds no additional meaning beyond what the schema provides, such as format examples or sourcing guidance, so it meets the baseline for high schema coverage.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('retrieve details') and target resource ('specific voice'), which is a specific verb+resource combination. However, it doesn't distinguish this tool from other 'get' siblings like 'retell_get_agent' or 'retell_get_call' beyond the resource type, missing explicit differentiation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives. For example, it doesn't mention if this should be used after listing voices with 'retell_list_voices' or in what contexts retrieval is needed, leaving the agent without usage context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_import_phone_numberC

Import an existing phone number from an external provider via SIP.

ParametersJSON Schema
NameRequiredDescriptionDefault
phone_numberYesThe phone number to import in E.164 format
termination_uriYesSIP termination URI for the phone number
inbound_agent_idNoOptional: Agent ID for inbound calls
outbound_agent_idNoOptional: Agent ID for outbound calls

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions 'import' and 'via SIP,' implying a mutation operation, but fails to describe critical behaviors like required permissions, whether this action is reversible, potential costs or rate limits, or what happens on success/failure. This leaves significant gaps for an agent to understand the tool's impact.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without any wasted words. It is front-loaded with the core action and resource, making it easy to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity of importing a phone number (a mutation operation with no annotations and no output schema), the description is incomplete. It lacks details on behavioral traits (e.g., side effects, error handling), output expectations, and usage context. For a tool with 4 parameters and potential integration implications, this minimal description falls short of providing adequate guidance.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents all parameters (phone_number, termination_uri, inbound_agent_id, outbound_agent_id) with clear descriptions. The description adds no additional meaning beyond what the schema provides, such as explaining the relationship between parameters or usage examples. The baseline of 3 is appropriate when the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('import') and resource ('existing phone number from an external provider via SIP'), making the purpose understandable. However, it doesn't explicitly differentiate from sibling tools like 'retell_create_phone_number' (which likely creates new numbers rather than importing existing ones), so it misses full sibling distinction.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives (e.g., 'retell_create_phone_number' for new numbers or other import methods). It lacks context about prerequisites, such as needing an external provider setup, or exclusions for when not to use it.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_list_agentsA

List all voice agents in your Retell account.

ParametersJSON Schema
NameRequiredDescriptionDefault

No parameters

TDQS

A3.7/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden. It mentions 'List all' but doesn't disclose behavioral traits like whether this is a read-only operation, if it requires authentication, potential rate limits, or the format of returned data. For a tool with zero annotation coverage, this leaves significant gaps in understanding how it behaves.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, front-loaded sentence that directly states the tool's purpose without any unnecessary words. It's appropriately sized for a simple list operation, making it easy to parse and understand immediately.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's simplicity (0 parameters, no output schema), the description is adequate but not complete. It lacks details on behavioral aspects like authentication needs, response format, or pagination, which would be helpful for an AI agent to use it correctly. Without annotations or output schema, more context would improve completeness.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool has 0 parameters with 100% schema description coverage, so no parameter documentation is needed. The description doesn't add parameter semantics, but this is appropriate given the lack of parameters. A baseline of 4 is assigned as the description doesn't need to compensate for any parameter gaps.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the specific action ('List all') and resource ('voice agents in your Retell account'), making the purpose immediately understandable. It distinguishes this tool from siblings like 'retell_get_agent' (which retrieves a single agent) and 'retell_list_chat_agents' (which lists a different type of agent), providing precise scope.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies usage for retrieving all voice agents, but doesn't explicitly state when to use this versus alternatives like 'retell_get_agent' for specific agents or 'retell_list_chat_agents' for chat agents. No guidance on prerequisites, pagination, or rate limits is provided, leaving usage context incomplete.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_list_callsC

List and filter calls with pagination support. Can filter by agent, status, time range, and more.

ParametersJSON Schema
NameRequiredDescriptionDefault
filter_criteriaNoOptional filter criteria
limitNoNumber of results to return (default: 50, max: 1000)
pagination_keyNoPagination key from previous response for fetching next page
sort_orderNoSort order by start timestamp

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions 'pagination support' and filtering, which is useful, but lacks critical details: it doesn't specify if this is a read-only operation, potential rate limits, authentication requirements, or what happens with large datasets. The description is too vague for a tool with multiple parameters and no annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise and front-loaded, stating the core purpose in the first clause. It uses two sentences efficiently, with no wasted words. However, it could be slightly more structured by explicitly separating listing from filtering aspects.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity (4 parameters, nested objects, no output schema, and no annotations), the description is incomplete. It covers basic functionality but misses behavioral traits, usage context, and output details. It's adequate as a minimal overview but lacks depth for effective tool selection and invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The description adds minimal value beyond the input schema, which has 100% coverage. It mentions filtering by 'agent, status, time range, and more,' which loosely maps to 'filter_criteria' parameters, but doesn't explain syntax, defaults, or interactions. With high schema coverage, the baseline is 3, as the schema already documents parameters well.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'List and filter calls with pagination support.' It specifies the verb ('list and filter'), resource ('calls'), and key capability ('pagination support'), which is specific and actionable. However, it doesn't explicitly differentiate from sibling tools like 'retell_get_call' or 'retell_list_chats', which slightly reduces clarity.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It mentions filtering capabilities but doesn't specify scenarios, prerequisites, or exclusions. For example, it doesn't clarify if this is for bulk retrieval versus single-call lookups or how it compares to 'retell_get_call' for individual calls.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_list_chat_agentsB

List all chat agents in your account.

ParametersJSON Schema
NameRequiredDescriptionDefault

No parameters

TDQS

B3.2/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden but only states the basic operation. It doesn't disclose behavioral traits like pagination, rate limits, authentication requirements, sorting/filtering capabilities, or what information is included in the listing. 'List all' implies comprehensive retrieval but lacks operational details.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that states the core purpose without any wasted words. It's appropriately sized for a simple listing operation and front-loads the essential information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a zero-parameter listing tool with no output schema, the description provides the basic purpose but lacks important context. Without annotations or output schema, it should ideally mention what information is returned (agent IDs, names, statuses) and any operational constraints. The description is minimally adequate but has clear gaps.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool has 0 parameters with 100% schema description coverage, so the description appropriately doesn't discuss parameters. The baseline for zero parameters is 4, as no parameter information is needed beyond what the empty schema already indicates.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('List all') and resource ('chat agents in your account'), providing a specific verb+resource combination. However, it doesn't distinguish this tool from sibling 'retell_list_agents' which appears to serve a similar purpose for general agents versus chat-specific agents.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided about when to use this tool versus alternatives. There's no mention of sibling tools like 'retell_list_agents' or 'retell_get_chat_agent', nor any context about when this listing operation is appropriate versus retrieving individual agents.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_list_chatsC

List all chat sessions with optional filtering.

ParametersJSON Schema
NameRequiredDescriptionDefault
limitNoNumber of results to return
pagination_keyNoPagination key for fetching next page

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden. It mentions 'optional filtering' but doesn't clarify what filtering options exist, whether this is a read-only operation, if there are rate limits, or what the output format looks like. The description is too vague to provide adequate behavioral context.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence with zero wasted words. It's appropriately sized for a simple list operation and front-loads the essential information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a list tool with no annotations and no output schema, the description is insufficient. It doesn't explain what constitutes a 'chat session', what fields are returned, or how filtering works. With 2 parameters and many sibling tools, more context is needed for the agent to use this effectively.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents both parameters (limit and pagination_key). The description adds no additional parameter information beyond what's in the schema, maintaining the baseline score of 3.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb ('List') and resource ('all chat sessions'), making the purpose understandable. However, it doesn't distinguish this tool from sibling list tools like 'retell_list_calls' or 'retell_list_chat_agents', which reduces differentiation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description mentions 'optional filtering' but provides no guidance on when to use this tool versus alternatives. With many sibling list tools available, there's no indication of what makes this specific to chat sessions or when to choose it over other listing tools.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_list_conversation_flowsB

List all conversation flows.

ParametersJSON Schema
NameRequiredDescriptionDefault

No parameters

TDQS

B3.2/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden of behavioral disclosure. 'List all conversation flows' implies a read-only operation, but it doesn't specify whether this requires authentication, returns paginated results, includes metadata, or has rate limits. For a tool with zero annotation coverage, this leaves significant behavioral gaps.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence with zero wasted words. It's front-loaded with the core action ('List all conversation flows') and doesn't include unnecessary details. Every word earns its place, making it easy for an agent to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's simplicity (0 parameters, no output schema), the description is minimally adequate. It states what the tool does but lacks context about the return format, authentication needs, or error handling. Without annotations or output schema, the agent must assume basic list behavior, which is sufficient but not complete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool has 0 parameters with 100% schema description coverage, so the schema fully documents the absence of inputs. The description doesn't need to add parameter information, and it correctly implies no filtering or arguments are required. A baseline of 4 is appropriate for parameterless tools when the schema is complete.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb ('List') and resource ('all conversation flows'), making the purpose immediately understandable. It distinguishes itself from sibling tools like 'retell_get_conversation_flow' (singular retrieval) by indicating it returns multiple items. However, it doesn't specify the scope or format of the listing, which prevents a perfect score.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites, context for listing flows, or differentiate from similar list tools like 'retell_list_agents' or 'retell_list_calls'. Without any usage instructions, the agent must infer context from the tool name alone.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_list_knowledge_basesB

List all knowledge bases.

ParametersJSON Schema
NameRequiredDescriptionDefault

No parameters

TDQS

B3.1/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden. It states the tool lists knowledge bases but doesn't disclose behavioral traits like pagination, rate limits, authentication requirements, or what 'all' entails (e.g., active only, includes metadata). For a list operation with zero annotation coverage, this is inadequate.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence with no wasted words. It's front-loaded and directly states the tool's purpose without unnecessary elaboration.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's simplicity (0 parameters) but lack of annotations and output schema, the description is incomplete. It doesn't explain what the list returns (e.g., format, fields) or behavioral aspects like ordering or limits, which are important for a list operation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool has 0 parameters with 100% schema description coverage, so no parameter documentation is needed. The description doesn't add parameter details, which is appropriate given the empty schema, earning a baseline score of 4 for this dimension.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description 'List all knowledge bases' clearly states the action (list) and resource (knowledge bases). It distinguishes from siblings like retell_get_knowledge_base (singular) and retell_create_knowledge_base (creation), but doesn't explicitly mention scope or filtering compared to other list tools like retell_list_agents.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives. The description doesn't mention prerequisites, context for listing knowledge bases, or when to choose this over other list tools (e.g., retell_list_agents).

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_list_llmsB

List all Retell LLM configurations.

ParametersJSON Schema
NameRequiredDescriptionDefault

No parameters

TDQS

B3.2/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden. It states a read operation ('List'), implying it's non-destructive, but doesn't disclose behavioral traits like pagination, rate limits, authentication needs, or output format. This is a significant gap for a tool with zero annotation coverage.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without any wasted words. It's appropriately sized and front-loaded, making it easy for an agent to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's low complexity (0 parameters, no output schema, no annotations), the description is minimally adequate but lacks completeness. It doesn't cover behavioral aspects like output format or usage context, which are important even for simple tools, leaving gaps in understanding.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool has 0 parameters with 100% schema description coverage, so the schema fully documents the inputs. The description adds no parameter information, which is acceptable given the baseline of 4 for zero parameters, as it doesn't need to compensate for any gaps.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb ('List') and resource ('all Retell LLM configurations'), making the purpose specific and understandable. It distinguishes from siblings like 'retell_get_llm' (which fetches a single LLM) by indicating it retrieves multiple items, though it doesn't explicitly compare to other list tools like 'retell_list_agents'.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites, context for listing LLMs, or differentiate from other list tools in the sibling set, leaving the agent to infer usage based on the name alone.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_list_phone_numbersB

List all phone numbers registered with your Retell account.

ParametersJSON Schema
NameRequiredDescriptionDefault

No parameters

TDQS

B3.2/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden. It states this is a listing operation, implying it's likely read-only and non-destructive, but doesn't explicitly confirm this or disclose other behavioral traits like pagination, rate limits, authentication requirements, or what data is returned. For a tool with zero annotation coverage, this leaves significant gaps.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, clear sentence that efficiently conveys the core purpose without any wasted words. It's appropriately sized for a simple listing tool and front-loads the essential information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's simplicity (0 parameters, no output schema), the description is minimally adequate but incomplete. It states what the tool does but lacks context about the return format, pagination, or behavioral constraints. With no annotations and no output schema, the description should provide more guidance on what to expect from the operation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool has 0 parameters with 100% schema description coverage, so the schema fully documents the absence of inputs. The description appropriately doesn't mention parameters, which aligns with the schema. A baseline of 4 is applied since no parameters exist and the description doesn't need to compensate for any gaps.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('List all') and resource ('phone numbers registered with your Retell account'), providing a specific verb+resource combination. However, it doesn't explicitly differentiate from sibling tools like 'retell_get_phone_number' (singular) or 'retell_import_phone_number', which would be needed for a perfect score.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention when this listing operation is appropriate compared to getting a specific phone number, importing numbers, or other related operations, leaving the agent without contextual usage instructions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_list_voicesB

List all available voices for use with agents.

ParametersJSON Schema
NameRequiredDescriptionDefault

No parameters

TDQS

B3.4/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden but only states the action without behavioral details. It doesn't disclose whether this is a read-only operation, its rate limits, authentication needs, or output format. For a tool with zero annotation coverage, this leaves significant gaps in understanding its behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without any fluff. It's front-loaded and every word contributes to understanding, making it optimally concise for a simple list operation.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's simplicity (0 parameters, no output schema), the description is minimally adequate but lacks depth. Without annotations or output schema, it should ideally mention the return format or behavioral constraints to be more complete, though it suffices for basic understanding.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool has 0 parameters with 100% schema description coverage, so no parameter documentation is needed. The description appropriately doesn't discuss parameters, earning a baseline score of 4 for not adding unnecessary information beyond the empty schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb ('List') and resource ('all available voices'), specifying their purpose for use with agents. It distinguishes from siblings like 'retell_get_voice' (which likely fetches a single voice) by implying a comprehensive listing, though it doesn't explicitly name alternatives.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies usage when needing voices for agents, but provides no explicit guidance on when to use this tool versus alternatives like 'retell_get_voice' or other list tools. It lacks context about prerequisites or exclusions, leaving usage inferred rather than clearly defined.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_publish_agentC

Publish/deploy the current agent configuration as a new version.

ParametersJSON Schema
NameRequiredDescriptionDefault
agent_idYesThe agent ID to publish

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. It implies a mutation ('publish/deploy') but doesn't specify whether this is reversible, what permissions are required, if it affects live systems, or what happens after publishing. The description lacks critical behavioral details for a deployment tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It is appropriately sized and front-loaded, with every word contributing to understanding the action.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a deployment/mutation tool with no annotations and no output schema, the description is incomplete. It doesn't explain what 'publish/deploy' entails operationally, what the new version means, or what the expected outcome is. This leaves significant gaps in understanding the tool's behavior and impact.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, with the single parameter 'agent_id' documented as 'The agent ID to publish'. The description adds no additional parameter semantics beyond what the schema provides, so it meets the baseline score of 3 for high schema coverage.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('publish/deploy') and target ('current agent configuration as a new version'), making the purpose understandable. It doesn't explicitly differentiate from siblings like 'retell_update_agent' or 'retell_get_agent_versions', but the verb 'publish/deploy' suggests a deployment action rather than modification or retrieval.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing agent configuration), exclusions, or how it differs from sibling tools like 'retell_update_agent' or 'retell_get_agent_versions', leaving the agent to infer usage context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_register_phone_callB

Register an inbound call from a custom telephony provider.

ParametersJSON Schema
NameRequiredDescriptionDefault
agent_idYesThe agent ID to handle the call
from_numberYesThe caller's phone number
to_numberYesThe called number
metadataNoOptional metadata for the call

TDQS

B3.3/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden for behavioral disclosure. While 'register' suggests a write operation, it doesn't explain what happens after registration (e.g., does it initiate the call, create a call record, trigger notifications?), nor does it mention authentication requirements, rate limits, or error conditions.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that clearly states the tool's purpose without unnecessary words. It's appropriately sized and front-loaded with the essential information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a write operation with no annotations and no output schema, the description provides basic purpose but lacks important context about what happens after registration, expected responses, error handling, or integration specifics. It's minimally adequate but leaves significant gaps for a tool that creates/mutates call data.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so parameters are fully documented in the schema. The description doesn't add any additional parameter context beyond what the schema provides, such as format requirements for phone numbers or examples of metadata usage. Baseline 3 is appropriate when schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('register') and resource ('inbound call'), specifying it's for calls from custom telephony providers. It doesn't explicitly differentiate from sibling tools like 'retell_create_phone_call', but the focus on 'inbound' and 'custom telephony provider' provides reasonable distinction.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies usage context ('inbound call from a custom telephony provider'), suggesting this is for integrating external phone systems rather than creating calls directly. However, it doesn't provide explicit guidance on when to use this versus alternatives like 'retell_create_phone_call' or mention prerequisites.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_update_agentC

Update configuration for an existing voice agent.

ParametersJSON Schema
NameRequiredDescriptionDefault
agent_idYesThe agent ID to update
agent_nameNoNew display name
voice_idNoNew voice ID
languageNoNew language code
webhook_urlNoNew webhook URL
interruption_sensitivityNoNew interruption sensitivity
enable_backchannelNoEnable/disable backchannel

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden but offers minimal behavioral insight. It states this is an update operation (implying mutation) but doesn't disclose permission requirements, whether changes are reversible, rate limits, error conditions, or what happens to unspecified fields. For a mutation tool with zero annotation coverage, this leaves critical behavioral aspects undocumented.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It's appropriately sized for a straightforward update operation and is front-loaded with the essential information. Every word earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a mutation tool with 7 parameters, no annotations, and no output schema, the description is insufficiently complete. It doesn't explain what 'configuration' entails beyond the parameter list, doesn't describe the update behavior (partial vs. full updates), and provides no information about return values or error handling. The agent lacks critical context for proper tool invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema description coverage is 100%, so all parameters are documented in the schema itself. The description adds no additional parameter semantics beyond what's already in the schema descriptions. This meets the baseline of 3 since the schema does the heavy lifting, but the description doesn't enhance understanding of parameter relationships or constraints.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Update configuration') and resource ('existing voice agent'), making the purpose immediately understandable. It distinguishes this from creation tools like 'retell_create_agent' by specifying 'existing', but doesn't explicitly differentiate from other update tools like 'retell_update_chat_agent' or 'retell_update_llm' beyond the resource type.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing agent), when not to use it, or how it differs from other update tools for different resource types. The agent must infer usage from the tool name and sibling list alone.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_update_callC

Update call metadata or data storage settings for a specific call.

ParametersJSON Schema
NameRequiredDescriptionDefault
call_idYesThe unique identifier of the call to update
metadataNoNew metadata to set for the call
data_storage_settingNoData retention policy for the call

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. It states this is an update operation (implying mutation) but doesn't cover critical aspects like required permissions, whether changes are reversible, error conditions (e.g., invalid call_id), or response format. For a mutation tool with zero annotation coverage, this leaves significant gaps in understanding behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It's front-loaded with the core action ('update') and resource ('call'), making it easy to parse. Every word earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given this is a mutation tool with no annotations and no output schema, the description is incomplete. It doesn't explain what happens on success (e.g., returns updated call object) or failure, security implications, or side effects. For a tool that modifies call data, more context is needed to use it effectively.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents all three parameters (call_id, metadata, data_storage_setting) with their types and descriptions. The description adds no additional semantic context beyond what's in the schema (e.g., format examples, constraints, or interactions between parameters). Baseline 3 is appropriate when the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('update') and the target ('call metadata or data storage settings for a specific call'), making the purpose understandable. It distinguishes this from sibling tools like 'retell_get_call' (read) and 'retell_delete_call' (delete), but doesn't explicitly differentiate from other update tools like 'retell_update_agent' or 'retell_update_phone_number' beyond the resource type.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing call ID), compare with other update tools (e.g., 'retell_update_agent' for agents), or indicate when metadata vs. data storage settings should be updated. Usage is implied by the name but not explicitly stated.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_update_chat_agentC

Update a chat agent's configuration.

ParametersJSON Schema
NameRequiredDescriptionDefault
agent_idYesThe chat agent ID to update
agent_nameNoNew display name
webhook_urlNoNew webhook URL

TDQS

C2.7/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states 'Update' implies a mutation, but doesn't disclose critical traits: whether it requires specific permissions, if changes are reversible, what happens to unspecified fields (partial vs. full updates), or error handling. For a mutation tool with zero annotation coverage, this is a significant gap in transparency.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's function without unnecessary words. It's front-loaded with the core action and resource, making it easy to parse quickly. Every part of the sentence earns its place by conveying essential information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity as a mutation operation with no annotations and no output schema, the description is incomplete. It lacks details on behavioral aspects (e.g., side effects, permissions), usage context, and what to expect upon success or failure. For a tool that modifies resources, this minimal description leaves too many gaps for reliable agent operation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The description doesn't add meaning beyond the input schema, which has 100% coverage with clear parameter descriptions (e.g., 'agent_id' as the ID to update, 'agent_name' as new display name). Since schema coverage is high, the baseline is 3, as the schema adequately documents parameters without needing extra explanation in the description.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose3/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states the action ('Update') and resource ('a chat agent's configuration'), which provides a basic understanding of purpose. However, it's vague about what 'configuration' entails and doesn't differentiate from sibling tools like 'retell_update_agent' or 'retell_update_conversation_flow', which likely update different types of agents or configurations. The description is functional but lacks specificity.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing agent), exclusions (e.g., what can't be updated), or comparisons to siblings like 'retell_update_agent' (which may update a different agent type) or 'retell_get_chat_agent' (for reading). Without such context, an agent must infer usage from the name alone.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_update_conversation_flowC

Update a conversation flow.

ParametersJSON Schema
NameRequiredDescriptionDefault
conversation_flow_idYesThe conversation flow ID to update
nameNoNew name
nodesNoUpdated nodes
edgesNoUpdated edges

TDQS

C2.7/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states 'Update' which implies a mutation, but lacks details on permissions required, whether updates are partial or full, side effects (e.g., on active conversations), or response format. This is inadequate for a mutation tool with zero annotation coverage.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence with zero wasted words. It's appropriately sized for a simple update operation and front-loaded with the core action, making it easy to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity of updating a conversation flow (likely involving structured data like nodes and edges), no annotations, and no output schema, the description is incomplete. It fails to explain behavioral aspects, usage context, or what the update entails beyond the basic verb, leaving significant gaps for an AI agent to understand and invoke the tool correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the input schema already documents all parameters (conversation_flow_id, name, nodes, edges) with descriptions. The tool description adds no additional meaning beyond what the schema provides, such as explaining what 'nodes' and 'edges' represent or their structure, resulting in a baseline score of 3.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose3/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states the action ('Update') and resource ('a conversation flow'), which provides a basic understanding of purpose. However, it's vague about what constitutes a 'conversation flow' and doesn't distinguish this tool from sibling tools like 'retell_update_agent' or 'retell_update_chat_agent' in terms of what specific resource it operates on.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. There are no mentions of prerequisites (e.g., needing an existing conversation flow ID), exclusions, or comparisons to sibling tools like 'retell_create_conversation_flow' or 'retell_delete_conversation_flow', leaving usage context unclear.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_update_llmC

Update a Retell LLM configuration.

ParametersJSON Schema
NameRequiredDescriptionDefault
llm_idYesThe LLM configuration ID to update
modelNoNew base model
general_promptNoNew system prompt
begin_messageNoNew greeting message

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. While 'Update' implies a mutation operation, the description doesn't disclose important behavioral traits: whether this requires specific permissions, whether changes are reversible, what happens to existing configuration fields not mentioned, or what the response looks like. For a mutation tool with zero annotation coverage, this is a significant gap.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that states the core purpose without any wasted words. It's appropriately sized for a straightforward update operation and gets directly to the point with no unnecessary elaboration.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a mutation tool with no annotations and no output schema, the description is incomplete. It doesn't address behavioral aspects like permissions, side effects, or response format. While the schema covers parameters well, the overall context for using this tool safely and effectively is insufficient given its complexity as an update operation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The description provides no parameter information beyond what's already in the schema. However, with 100% schema description coverage, all four parameters (llm_id, model, general_prompt, begin_message) are well-documented in the schema itself. The baseline score of 3 reflects adequate parameter documentation through the schema alone, though the description adds no additional semantic context.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb ('Update') and resource ('a Retell LLM configuration'), making the purpose immediately understandable. It distinguishes this as an update operation rather than creation or deletion, though it doesn't explicitly differentiate from sibling update tools like retell_update_agent or retell_update_conversation_flow.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing LLM configuration), doesn't specify when this is appropriate versus creating a new LLM, and doesn't reference sibling tools for comparison or complementary operations.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

retell_update_phone_numberC

Update settings for a phone number including assigned agents.

ParametersJSON Schema
NameRequiredDescriptionDefault
phone_numberYesThe phone number in E.164 format to update
inbound_agent_idNoNew agent ID for inbound calls (null to remove)
outbound_agent_idNoNew agent ID for outbound calls (null to remove)
nicknameNoNew nickname for the phone number

TDQS

C2.9/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden. It states this is an update operation, implying mutation, but doesn't disclose behavioral traits like required permissions, whether changes are reversible, rate limits, or error handling. The description adds minimal context beyond the basic action, leaving significant gaps for a mutation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that front-loads the core action and key fields. It avoids unnecessary words and gets straight to the point. However, it could be slightly more structured by explicitly listing updatable fields, but it's appropriately concise for the tool's complexity.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given this is a mutation tool with no annotations and no output schema, the description is incomplete. It lacks details on behavioral aspects (e.g., side effects, permissions), usage context, and response format. While the schema covers parameters well, the overall context for safe and effective use is insufficient, especially for an update operation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents all parameters thoroughly. The description adds marginal value by mentioning 'assigned agents' (hinting at inbound_agent_id and outbound_agent_id) and 'settings' (implying nickname and other fields), but doesn't provide additional meaning beyond what's in the schema. Baseline 3 is appropriate as the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Update settings') and resource ('phone number'), specifying what fields can be updated ('including assigned agents'). It distinguishes from sibling tools like retell_create_phone_number (create vs update) and retell_delete_phone_number (delete vs update), though it doesn't explicitly mention these distinctions. The purpose is specific but could be more precise about scope.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No explicit guidance on when to use this tool versus alternatives is provided. The description implies usage for modifying phone number settings, but it doesn't mention prerequisites (e.g., phone number must exist), exclusions, or compare to tools like retell_update_agent for agent-specific changes. Usage is implied from the action, but no contextual advice is given.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

TDQS

B3.2/5.0
Disambiguation4/5

Most tools have distinct purposes targeting specific resources and actions, such as create_agent vs. update_agent. However, some overlap exists between retell_create_chat and retell_create_chat_completion, where the distinction between starting a chat and sending a message might be ambiguous without careful reading of descriptions. Overall, the set is well-organized but has minor confusion points.

Naming Consistency5/5

All tools follow a consistent verb_noun pattern with the prefix 'retell_' and snake_case throughout, such as retell_create_agent, retell_list_calls, and retell_update_phone_number. This uniformity makes the tool set predictable and easy to navigate, with no deviations in naming conventions.

Tool Count2/5

With 52 tools, the count is excessive for a single server, making it overwhelming and difficult for agents to manage. While the domain (Retell AI) is broad, the number of tools could be consolidated or better scoped, as many operations (e.g., create, get, update, delete, list) are repeated across multiple resource types, leading to redundancy.

Completeness5/5

The tool set provides comprehensive CRUD and lifecycle coverage for all major resources in the Retell AI domain, including agents, calls, chats, knowledge bases, LLMs, phone numbers, and conversation flows. There are no obvious gaps; each resource type has create, get, update, delete, and list operations, ensuring agents can handle full workflows without dead ends.

Maintenance

ActivityInactive
ResponsivenessNo issues

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