get_duration_stats

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

No annotations are provided, placing full burden on the description. It states what statistics are returned but fails to disclose behavioral traits such as being a read-only operation, data freshness, side effects, or any constraints. The description offers minimal transparency beyond the output values.

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 two sentences long and front-loaded with key information. The second sentence is slightly redundant ('Shows how long calls typically last' is implied by the first), but overall it is efficient and not verbose.

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?

With 5 parameters, no output schema, and no annotations, the description adequately explains the returned statistics but omits details like default behavior of date parameters, time zone handling, and output format. It is sufficient for basic use but lacks completeness for an agent to fully understand invocation context.

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%, so each parameter is documented. The description adds context about the statistics but does not provide additional meaning for the parameters themselves (e.g., format requirements or behavioral implications). Baseline of 3 is appropriate.

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 'call duration statistics', listing specific metrics (average, median, min, max, p95) and providing a concise summary. It effectively differentiates from sibling tools like 'get_call_volume' which focuses on counts rather than duration.

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 understanding call length but does not provide explicit guidance on when to use this tool versus alternatives like 'get_daily_summary' or 'get_call_outcomes'. It lacks 'when-to-use' and 'when-not-to-use' instructions.

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