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

Annotations already establish the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description's added value is the result behavior: cap of 10 results, the fields returned, and the ranking rule that IFRA-prohibited or EU-banned materials are flagged and ranked lower. This is meaningful behavioral context beyond the annotations. It stops short of covering zero-result or pagination behavior, so a 4 rather than 5.

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 trigger condition, then result behavior, then routing alternatives and exclusions. Every sentence earns its place — no filler, no restating of the title.

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?

There is no output schema, so the description carries the burden of describing returns, and it does so thoroughly: material types, returned fields, result cap, ranking rule, and page link. Combined with the sibling routing and exclusions, an agent has everything needed to call it correctly.

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 50%: the required 'query' param is documented in the schema itself, but 'limit' has no description anywhere. The description implies result-count capping ('up to 10') but never explains the limit parameter or its default/min/max interaction. It adds little semantic detail beyond the schema.

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/find) and resource (perfumery materials) with the dimensions searched: scent, family, name, CAS number. It explicitly distinguishes itself from get_material (single-material detail) and check_formula (whole-formula check), so an agent can route correctly without opening either 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?

Opens with an explicit 'Use this when...' trigger, gives concrete examples ('musks, woods or citrus', 'catalog name of a material they typed loosely'), names the two alternatives with their selecting conditions, and adds an exclusion ('Not for finished perfumes or shopping advice'). When/when-not/alternatives are all present.

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