retell_list_calls

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

Without annotations, the description relies on 'List' to signal a read-only operation, which is a weak but acceptable disclosure. It does not explicitly confirm non-destructive behavior, auth needs, or rate limits, but it does mention account scoping and supported features.

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: the first states the core purpose, and the second lists key capabilities. Every word earns its place, with no redundancy or filler.

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 list operation, the description covers the primary function, filters, and pagination in a concise way. Since there is no output schema, it could have briefly described the return format, but that's a minor gap given the tool's simplicity. Overall, it provides a solid baseline for an agent to select and use the tool.

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 the parameters are already fully documented. The description's mention of filtering by agent ID, status, and date range adds no new meaning beyond the schema; pagination_key is also already described in the schema.

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 opens with 'List calls in your Retell AI account' — a specific verb and resource. This clearly distinguishes it from siblings like retell_get_call (which retrieves a single call) and other list 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?

The description mentions supported filters and pagination, which implies when to use the tool, but it does not explicitly contrast with alternatives or state exclusions. There is no reference to when a different tool would be more appropriate.

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