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add_agent_tool

Add or update API-call tools on an agent so it can make HTTP requests to external APIs like order lookups, appointments, or CRM posts during a call. Upserts by name and supports batch via 'tools'.

Instructions

Add (or update) one or more API-call tools on a single_prompt agent. API-call tools let the agent make an HTTP request to an external API during a call — e.g. look up an order, book an appointment, or post to a CRM. The agent decides when to invoke a tool from its name + description, filling in any declared parameters. Pass a single tool via the top-level fields, or several at once via tools. Upserts by name: an existing tool with the same name is replaced, others are preserved. Changes are saved to the branch's draft via read-modify-write against the open draft — make tool edits one at a time (sequential edits stack; concurrent edits to the same branch can drop each other), then publish_draft once to make everything live. Use remove_agent_tool to delete a tool by name, and configure_call_actions for end_call / transfer_call.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
urlNoThe endpoint URL to call. May contain {{variable}} placeholders.
nameNoUnique tool name, no spaces (e.g. lookup_order). Re-using a name replaces that tool.
toolsNoBatch mode: multiple API-call tools to add/update in one write. When provided, the top-level single-tool fields are ignored.
methodNoHTTP method
enabledNo
headersNo
agent_idYesThe agent ID to add the tool(s) to
branch_idNoBranch whose draft to edit (from list_branches). Omit to use the live branch; if the agent has multiple branches you'll be asked to pick one.
parametersNo
timeout_msNo
descriptionNoWhat the tool does and when the agent should call it. This is the only guidance the LLM gets — be specific.
query_paramsNo
request_bodyNo
response_variablesNo
Behavior5/5

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

Without annotations, the description fully discloses behavior: upsert by name (replace existing), edits saved to draft via read-modify-write, concurrent edit risks, need to publish_draft to make live, and that the agent decides when to invoke based on name+description.

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 well-structured with front-loaded purpose and logical flow. It is informative but slightly verbose with minor redundancy. Each sentence adds value, but some details (e.g., 'API-call tools let the agent...') could be tighter. Still, it respects conciseness expectations.

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

Completeness5/5

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

Given the tool's complexity (14 parameters, nested objects, no output schema), the description covers all necessary context: what the tool does, how to use it, side effects (draft editing, upsert behavior, concurrency risks), and related tools. It is complete for an agent to select and invoke correctly.

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 description adds meaning beyond the schema by explaining the batch vs single-tool modes, the upsert behavior by name, and the workflow context. While schema coverage is 50%, the description does not detail every parameter but provides high-level guidance that aids parameter usage.

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 'Add (or update) one or more API-call tools on a single_prompt agent' and explains what API-call tools do with examples. It distinguishes from siblings by mentioning remove_agent_tool and configure_call_actions, leaving no ambiguity about its purpose.

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

Usage Guidelines5/5

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

It explicitly tells when to use (to let the agent make HTTP requests), how to use (single tool via top-level fields or batch via `tools`), and when not to (use remove_agent_tool for deletion, configure_call_actions for end_call/transfer_call). It also advises making edits one at a time and publishing drafts.

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

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