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

Description states the direct effect (volume set to zero) and is consistent with annotations (idempotent, not destructive). It adds little beyond the tool name, but annotations carry the safety profile; no contradiction or extra context like reversibility.

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?

Single sentence, densely packed, no filler. Front-loaded with the primary action and target.

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?

The tool is simple, has an output schema, and rich annotations. The description adequately identifies the single clip target; missing only explicit alternative guidance, but overall the context is sufficient for calling it.

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 covers projectId, idempotencyKey, and expectedRevision. Description clarifies timelineItemId as the target media item, compensating for the missing schema description. No additional syntax or relation to the optional expectedRevision is provided.

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 uses a specific verb ('Set') and precise resource ('one timeline media item's volume to zero'). It clearly distinguishes from sibling tools like timeline_audio_add or batch_update_timeline_clips by targeting a single clip's audio.

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 phrase 'one timeline media item' implies single-item usage, but the description does not explicitly state when to choose this over update_timeline_clip or batch_update_timeline_clips, nor any exclusions.

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