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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description adds the pitch-preservation behavior and the 0.5–2.0 range, but the phrase 'client and server side from freedailypro' is opaque and it omits the operation's permissions and result format.

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 front-loaded sentence with the core verb first, which is good, but the trailing 'client and server side from freedailypro' fragment is noise that muddies rather than informs.

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 two-parameter mutation-style tool with no output schema and 0% schema description coverage, the definition does not document the fileBase64 input, expected audio format, or what the tool returns. It is not complete enough for an agent to invoke confidently without guessing.

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 0%, so the description carries the full burden. It repeats the speed range already encoded as min/max in the schema but says nothing about 'fileBase64' — the agent must infer it is the source audio encoded as base64, and the expected encoding/format is undocumented.

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 ('Change audio playback speed') and adds a differentiating qualifier ('without altering pitch') that separates it from the sibling audio_pitch. The trailing 'client and server side from freedailypro' is confusing but does not obscure the core purpose.

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?

Usage is only implied: 'without altering pitch' hints that audio_pitch is the alternative for pitch changes, but the description never explicitly says when to pick this tool over audio_pitch or the other audio_* siblings. No prerequisites or exclusions are stated.

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