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

Annotations only declare readOnlyHint=true and openWorldHint=true. The description adds important behavioral context beyond those: the difference between precise and fast modes, keyframe cut behavior, and the per-call x402 cost.

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?

Three tightly written sentences front-load the operation, then parameter form, then mode tradeoff, then cost. Every sentence adds value with no repetition or filler.

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 9-parameter paid media tool with high schema coverage and no output schema, the description covers the core operation, input time formats, mode behavior, and cost. It does not repeat source input details already documented in the schema, so it is nearly complete.

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 already high (89%), so baseline is 3. The description still adds meaning: it explains that end can be seconds or hh:mm:ss, that duration can substitute for end, and that precise vs fast has concrete re-encode/copy consequences.

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: cut a clip out of an audio or video file, with clear scope via start/end or duration. The operation is easily distinguished from nearby media_* tools such as media_convert, media_extract_audio, media_gif, and media_thumbnail.

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?

Offers useful mode guidance: precise re-encodes for frame-exact cuts, fast copies streams and cuts on keyframes. However, it gives no explicit guidance on when to use this tool versus sibling tools like media_convert or media_extract_audio.

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