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 real behavioral value beyond that: it discloses the return shape (flat list, no product data) and an edge case (no genuine matches returns an empty result, not an error), which an agent cannot infer from annotations alone.

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: purpose first, routing to the alternative second, edge-case behavior last. No filler, everything front-loaded and earning its place.

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 an output schema present, return values need not be spelled out, and the description nonetheless characterizes the response (phrase list, empty-result behavior). Purpose, alternative, and edge case are all covered for a simple one-param tool.

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 a single documented 'q' parameter, so the schema already carries the parameter contract. The description reinforces that the input is a partial/prefix query but adds no syntax, length, or format detail beyond the schema. 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?

States a specific verb+resource (typeahead suggestions for a partial query) and explicitly scopes what is returned: a flat list of suggested search phrases, no product data. This cleanly separates it from siblings like quince_search and quince_product.

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 routes the agent: pass a suggestion straight through to quince_search's q parameter for product results, which tells the agent both when to use this tool (prefix/typeahead) and what the alternative is for actual product data.

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