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

Annotations cover readOnly/openWorld, but the description adds substantial context beyond them: the shape of the result (flat list of phrases with popularity score and live active-listing match count), the absence of listing data, and the notable failure behavior ('well-formed empty result rather than an error'). That empty-result guarantee is exactly the kind of edge-case disclosure annotations cannot provide.

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?

Three tight sentences front-loaded with the core definition, then the chaining instruction, then the edge-case behavior. No redundant restating of the name or annotations.

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 single-param typeahead tool with an output schema, the description covers purpose, chaining, output shape at a high level, and empty-result behavior. Nothing an agent needs to invoke 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 0% and there is one undocumented param 'q', so the description must compensate. It does so by describing the input as a 'partial query' (i.e. a prefix, not a full search string), which materially clarifies how to fill q, though it gives no length/format specifics.

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 and resource: 'Grailed's own search-box typeahead suggestions for a partial query.' It also distinguishes the output from siblings by specifying 'no listing data,' which separates it from grailed_search and grailed_sold_listings.

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 clear chaining guidance: 'Pass a suggestion straight through to grailed_search/grailed_sold_listings' own q parameter.' This tells the agent how to use the output, though it stops short of explicitly stating when to prefer this tool over calling search directly.

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