List calls

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint false, so no safety ambiguity. The description adds useful behavioral context beyond annotations: it returns summary data only, not transcripts, and requires the calls:read scope. This helps the agent understand what the call will and will not return.

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?

Three concise, information-dense sentences: scope qualifier, filter capabilities, single-call alternative, and auth requirement. Every sentence earns its place and the key differentiator is front-loaded.

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 12-parameter list tool with no output schema, the description covers purpose, filter categories, the correct alternative, and required scope. Pagination and individual param detail are handled by the schema. The only minor gap is that 'summary form' is somewhat vague about exact output fields, but it is sufficient for correctness.

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 documents 67% of parameters; the description adds a functional overview by grouping them into filter dimensions: status, direction, agent, campaign, engine, phone number, and time window. It does not add individual parameter detail beyond the schema, so it partially compensates but mostly relies on 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?

Description states a specific verb and resource: 'List calls', and adds a precise scope qualifier: 'in summary form (no transcript)'. It also names the alternative get_call for the full record, so an agent can distinguish list_calls from get_call and get_call_transScript without opening schemas.

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?

Provides a clear when-to-use context: list calls in summary form; if the full record of a single call is needed, use get_call. It does not explicitly mention get_call_transcript for transcripts, but the phrase '(no transcript)' plus 'full record' gives sufficient routing information.

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