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

Annotations only say readOnlyHint=false and openWorldHint=true; the description goes further by explaining that the write is a save-to-audio-library that returns a generation_id and audio_url usable by add_sound_to_video, and that it costs no tokens and is open to every account. That is genuine behavioral context the structured fields cannot convey.

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-loaded with the action and the search-first instruction, and every sentence carries a distinct fact (search, save, alternative). The semicolon-chained middle sentence is dense and forces a re-read, costing a little clarity.

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?

With no output schema and six optional parameters, the description still covers both modes, what a search returns (sound_id, title, seconds, artists, bpm, moods, genres), what a save returns (generation_id, audio_url), and where the result is consumed downstream. Nothing required to call it correctly 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 100%, so the baseline is 3, but the description adds the pairing relationship the schema only hints at: title and seconds must be echoed back alongside save_id so the saved sound keeps its name and length, and search is described as plain-language intent ('upbeat summer pop'). It clarifies how parameters combine into modes rather than just what each one is.

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 (find) and resource (licensed music tracks and sound effects in the Epidemic Sound catalogue), and explicitly contrasts itself with find_library_sound. An agent can distinguish it from generate_music, generate_sound_effect and find_library_sound without opening any schema.

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?

Gives an explicit two-step procedure (search first, then re-call with save_id), plus the exclusion rule: 'find_library_sound stays first for the small Switch Motion effects on the owner's account.' Both when-to-use and when-not-to-use are stated.

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