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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds genuine behavioral context beyond that: the exact shape of the result (phrases + popularity + live match count, no listing data) and the important edge case that a no-match query returns a well-formed empty result rather than an error, which prevents the agent from misreading an empty list as a failure.

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 what the tool is, then the return shape, then the chaining instruction, then the empty-result caveat. Every clause carries distinct information with no redundancy.

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?

Despite an output schema existing, the description independently characterizes the return payload and its no-match behavior. Combined with the clear chaining guidance and the single fully-documented parameter, nothing an agent needs 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%, with q already described as a 'Partial search query,' so the baseline is 3. The description reinforces 'partial query' and the pass-through usage but adds no format, length, or matching-syntax 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+resource ('search-box typeahead suggestions for a partial query') and pinpoints exactly what is returned — a flat list of suggested search phrases with a popularity score and live match count, explicitly 'no listing data.' This distinguishes it from grailed_search/grailed_sold_listings without opening their schemas.

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?

Explicitly instructs to 'pass a suggestion straight through to grailed_search/grailed_sold_listings' own q parameter,' naming the two alternatives it feeds and how to chain it. It clearly establishes the typeahead-before-search use case, though it doesn't spell out a when-not-to-use (e.g., full queries that should go directly to search).

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