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

Annotations declare non-destructive, idempotent, open-world behavior, which the description does not contradict. Beyond that, the description adds critical behavioral context: it produces a NEW audio_file_id, the free-plan API returns a 60-second head preview while the full render requires an editor click or paid plan, and the response indicates which was returned. This is rich disclosure beyond annotations.

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?

Compact and front-loaded: the first sentence defines the tool and its modes, subsequent sentences cover return value, integration, and free-tier caveats. Every sentence earns its place with no redundancy.

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?

Given six parameters, three enums, no output schema, and an open-world annotation set, the description covers the essential workflow (enhance original, get new ID, use in cast_build_project), the free-plan preview limitation, and the response meaning. Nothing critical for correct invocation is missing.

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 33%, so the description must compensate. It explains the three kind values, the strength options (subtle/medium/strong), and implies the pipeline choice via 'noise + room removal'. It does not clarify wait_seconds or preview_seconds, but the schema partially documents preview_seconds. Overall it adds significant meaning for the primary parameters.

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 title and description state a specific verb and resource — AI cleanup of a recording — and enumerate the three modes (speech, music, bg_music) with precise semantics for each. It is clearly distinguishable from siblings like cast_import_audio or cast_build_project.

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?

Explicit guidance: enhance the ORIGINAL upload, not an already-enhanced file; use the new audio_file_id as the voice source in cast_build_project; cuts planned on the original still apply. It also names the alternative path for full-length render (editor click vs paid API), leaving no ambiguity about when to use this tool.

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