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

Beyond the annotations' readOnly/idempotent/non-destructive profile, it discloses the auth requirement ("authenticated agent and active music_retrieval grant matching the current asset/index"), the result cap ("up to 20 matching source segments"), and failure behavior ("retain the returned error and request the appropriate access rather than retrying anonymously"). These are non-obvious operational traits an agent needs.

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?

Four sentences, well front-loaded with the core action first, then auth, returns, and fallback guidance. Dense and informative; slightly sprawling but each sentence carries real content, so little is wasted.

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, the description supplies the return shape (up to 20 segments with existing timestamp/method labels), the authorization precondition, and error-handling guidance. Nothing an agent needs to call this 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% and each parameter is documented in the schema, including notes that receipt_id and idempotency_key are not read. The description only restates "text query" and adds no syntax, matching, or format detail beyond what the schema already provides, so the baseline of 3 is appropriate.

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 ("Search") and resource ("indexed timestamped segment evidence for a text query"), and explicitly distinguishes itself from inspect_musicology and from measurement/listening tools. An agent can tell what this does and does not do without opening the 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?

Names a concrete alternative ("Use inspect_musicology for broad analysis metadata") and states when-not conditions ("it does not make new audio measurements or prove personal listening"). It gives clear context and one alternative, but does not route among the other retrieval siblings such as search_lyrics or get_song_dossier.

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