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

Adds substantial behavioral context beyond annotations: result links expire after one hour, the server downloads the public URL into temporary R2 storage, processes via a headless browser, and deletes the input when the job ends. This does not contradict destructiveHint=false because the deletion is of the server-side temporary copy, not the user's original file.

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?

Front-loads the purpose, then moves through input constraints, settings, output, and lifecycle. All sentences are relevant, though the infrastructure detail is more expansive than strictly needed for tool invocation.

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?

No output schema exists, but the description explains the returned download links and their expiry. The input schema covers file structure, yet the free-form settings object and acceptable speed/pitch values are not specified, leaving a small gap.

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 description coverage is 100%, so baseline is 3. The description repeats settings names (speed, keepPitch), output format examples, and bitrate, but adds little type or range detail; it also says 'one file' while the schema allows up to 12, creating minor ambiguity.

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?

States a specific verb and resource: changes playback speed, with or without pitch. The 'with or without changing pitch' phrasing distinguishes it at a high level from pure pitch-shifting or tempo-only 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 intended use case is implied by the name and capability, and input prerequisites are mentioned. However, there is no explicit when-to-use, when-not-to-use, or routing guidance against siblings such as pitch_shifter, tempo_changer, or audio_converter.

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