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 nonetheless adds real behavioral context: the multi-word AND matching rule and the fact that joining words such as 'by' are ignored, which tells the agent how results are actually derived.

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?

A single dense sentence, front-loaded with the verb and resource, with the matching rule and return fields trailing. It is efficient and waste-free, though the run-on clause structure makes it slightly harder to scan than a split sentence would be.

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-optional-parameter, closed-world read tool with an output schema, the description supplies what the schema cannot: matching semantics and a preview of returned fields. Nothing critical is missing, though an explicit note on result ordering/pagination would make it fully 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 coverage is 100%, so the query and language parameters are already fully documented in the schema, including the default language and the empty-query behavior. The description restates the query semantics but adds no syntax, format, or language-selection detail beyond what the schema provides; baseline 3 applies.

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?

The description names a specific verb and resource ('Search Cesure's catalog of free pieces') and goes further by specifying the match semantics (words of title and/or composer, stop-words like 'by' ignored). None of the sibling tools overlap with this read/search role, so an agent can distinguish it immediately.

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 implied by the description ('search ... catalog'), and the schema notes that an empty query lists the catalog, but there is no explicit statement of when to reach for this tool versus alternatives, nor any exclusion criteria. Adequate but leaves the routing inference to the agent.

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