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

Annotations already declare readOnly, idempotent, and non-destructive behavior. The description adds that the tool returns a 'real call recording URL' rather than audio content itself, which is useful context. It does not mention URL expiration, access restrictions, or whether the recording is always available, but annotations cover the safety profile.

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?

A single, focused sentence that explains both what the tool does and why it matters. No filler, front-loaded with the key purpose.

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 simple one-parameter read-only lookup with an output schema and clear annotations, the description is sufficient. It could mention URL expiration or auth requirements, but those are not critical for selection or invocation.

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%, and the single parameter call_id is already fully described in the schema. The description adds no additional meaning about the parameter beyond its existence, so it meets the baseline without providing extra value.

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 action ('Get'), the resource ('call recording URL'), and the purpose ('so reviewers can listen to the voice/audio'). It also differentiates from get_transcript by emphasizing audio over transcript.

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 when to use this tool: when reviewers need the actual voice/audio rather than the transcript, which differentiates it from the sibling get_transcript. However, it does not explicitly state when not to use it or name the alternative directly, so it falls just short of full guidance.

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