Telnyx

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

Annotations already indicate readOnlyHint=true and idempotentHint=true, so the description does not need to repeat safety info. The description adds that the schema is from the Telnyx TypeScript API and can be used for invocation, which is helpful context beyond the annotations.

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

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

The description is extremely concise with two sentences, no superfluous words, and the key information is front-loaded. Every sentence adds value.

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

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

Given the low complexity (one parameter, no output schema), the description fully covers what the tool does and how it fits into the workflow with the sibling tool. The purpose and return value are implied.

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

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

The schema has 100% coverage with a basic description for the single parameter 'endpoint'. The tool description does not add any additional detail about the parameter beyond what is already in the schema, so it meets the baseline of 3.

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

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

The description clearly states the verb 'Get' and the resource 'schema for an endpoint in the Telnyx TypeScript API'. It differentiates from siblings list_api_endpoints and invoke_api_endpoint by focusing on schema retrieval, not listing or invocation.

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

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

The description explicitly explains the usage workflow: use this tool to get a schema, then invoke the endpoint with invoke_api_endpoint. This provides clear context on when to use the tool, though it does not explicitly state when not to use it or mention alternatives.

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

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

Annotations already indicate destructiveHint=true, so description does not need to repeat that. Description adds no further behavioral details (e.g., rate limits, authentication) beyond annotations. Neither contradicts nor enriches.

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

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

Two efficient sentences: first states purpose, second provides critical usage guidance. No superfluous information.

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

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

Given the dynamic nature of endpoints from an external API, the description adequately references sibling tools for details. Lacks return format info but acceptable given openWorldHint=true and no output schema.

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

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

Schema coverage is 100%, so baseline is 3. Description adds value by stating that args must match the schema from get_api_endpoint_schema, which helps the agent understand the expected input format beyond the default schema description.

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

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

Description clearly states 'Invoke an endpoint in the Telnyx TypeScript API' with a specific verb and resource. It distinguishes from siblings by referencing list_api_endpoints and get_api_endpoint_schema as prerequisite tools.

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

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

Explicitly instructs users to first use list_api_endpoints and get_api_endpoint_schema to obtain the endpoint list and schema, providing clear context for proper usage. Does not explicitly state when not to use this tool, but implication is clear.

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

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

Annotations already provide readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is clear. The description adds no additional behavioral details (e.g., pagination, rate limits, or response structure), making it minimally additive beyond annotations.

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

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

The description is a single concise sentence, front-loaded with the verb 'List or search'. It is efficient, though it could be slightly more specific (e.g., 'all endpoints' vs. just 'endpoints').

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

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

Given the tool's simplicity (no required params, no output schema, and clear annotations), the description adequately conveys the tool's purpose and basic usage. It is complete enough for a list/search operation.

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

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

Schema coverage is 100% with a single parameter search_query that includes a description. The description repeats the search/filter concept but adds no new semantic information beyond what the schema provides.

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

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

The description clearly states the action (list or search), the resource (all endpoints in the Telnyx TypeScript API), and distinguishes from sibling tools like get_api_endpoint_schema (which focuses on a single endpoint schema) and invoke_api_endpoint (which performs an invocation).

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

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

The description implies use for discovering endpoints, but does not explicitly state when to use this tool versus alternatives, nor does it provide when-not conditions. It leaves context inference to the agent.

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

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is clear. The description adds that it opens an app, which aligns with these hints. No contradictions, and no additional behavioral traits needed.

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

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

The description is a single, concise sentence that is front-loaded with the key action and resource. Every word is meaningful, no fluff.

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

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

Given the simplicity of the tool (open an app, no output schema, single optional parameter), the description is sufficiently complete. It explains the purpose and the action, and annotations cover safety. No critical gaps.

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

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

Schema coverage is 100% with a single optional action parameter. The schema already describes it as 'Optional no-op app opener action'. The description does not add further meaning beyond what the schema provides.

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

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

The description clearly states the verb 'Open' and the resource 'Telnyx Number Intelligence MCP App', and specifies the workflow context (lookup, validation, enrichment). This distinguishes it from sibling tools which are about API endpoints or monitors.

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

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

The description implies this tool is for opening the app, but does not explicitly state when to use it vs. alternatives, nor does it provide when-not or exclusion guidance. Contextually, it's clear from sibling names, but no explicit guidelines.

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

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the agent knows it's a safe read operation. The description adds that it 'opens' an app, which is consistent. No additional behavioral traits are disclosed beyond the app launch.

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

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

Single sentence, front-loaded, and concise. No wasted words, though it could be slightly more informative about the app's scope.

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

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

Given the tool's simplicity (no required params, no output schema), the description is complete enough. It tells the agent to open the app for cost analysis, and annotations cover safety. No additional context like return values is needed.

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

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

Schema description coverage is 100%, with one optional parameter (action) fully documented via enum and default. The description does not add any meaning beyond the schema; it does not explain the parameter or its effect.

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

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

The description clearly states the tool opens the Telnyx Usage & Cost Explorer for cost analysis, specifying the app name and purpose. However, it does not explicitly differentiate from siblings like open_number_intelligence and open_voice_monitor, which also open apps. The distinct app name 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.

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., open_number_intelligence for numbers, open_voice_monitor for voice). There are no when-to-use or when-not-to-use instructions, nor mention of prerequisites or context.

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

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

Annotations already indicate read-only, idempotent, and non-destructive behavior. The description adds that opening the app is for observation/troubleshooting, which is consistent and provides minimal additional behavioral context beyond annotations.

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

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

The description is a single sentence with 12 words, front-loading the key information about the tool's action and purpose. No unnecessary words.

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

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

For a simple open-app tool with no output schema and clear annotations, the description is complete enough. It could optionally mention the optional action parameter, but the schema covers that. The context of voice traffic monitoring is useful.

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

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

Schema coverage is 100% and the parameter 'action' is fully described with enum and default in the schema. The description does not add any parameter-specific meaning, 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.

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

The description clearly identifies the tool's action ('Open'), the specific resource ('Telnyx Voice Monitor MCP App'), and its purpose ('observing and troubleshooting voice traffic'). It distinguishes from siblings like 'open_number_intelligence' and 'open_usage_cost_explorer' by naming the app.

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

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

The description implies usage for voice traffic observation and troubleshooting but does not explicitly state when to use this tool vs alternatives like open_number_intelligence or invoke_api_endpoint. No exclusions or prerequisites are mentioned.

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