hangup

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 action ('hang up a call') which implies a destructive write operation, but doesn't disclose important behavioral traits like whether this requires specific permissions, what happens to the call participants, whether the action is reversible, or any rate limits. The mention of 'Response data' is too vague to be helpful.

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 appropriately concise with three sentences that cover purpose, parameters, and return value. It's front-loaded with the core purpose. However, the parameter section contains incorrect information that undermines its efficiency.

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 destructive call control tool with no annotations, 0% schema coverage, no output schema, and a complex nested parameter structure, the description is inadequate. It doesn't explain the actual parameter structure ('request' object), provides misleading parameter information, and gives no insight into what the response contains or the tool's behavior beyond the basic action.

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 0%, and the description mentions 'call_control_id: Required. Call control ID.' However, the actual input schema has only one parameter named 'request' (an object), not 'call_control_id'. This creates a direct contradiction between the description and the actual schema, making the parameter information misleading rather than helpful.

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's purpose with a specific verb ('hang up') and resource ('a call'), making it immediately understandable. However, it doesn't distinguish this tool from potential sibling call-related tools like 'transfer' or 'playback_stop' in terms of call termination vs. other call control actions.

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 about when to use this tool versus alternatives. With sibling tools like 'transfer', 'playback_stop', and 'make_call' available, the description doesn't indicate that this is specifically for terminating active calls versus transferring them or stopping media playback.

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