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

The description goes well beyond the annotations (readOnlyHint, openWorldHint) by disclosing authentication-dependent data access, the null value for unanswered questions, pagination behavior with limit and next_cursor, the not_found response for missing listings, and the untrusted data warning. This is rich behavioral context that an agent needs to handle responses correctly.

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?

The description is concise yet information-dense. Each sentence adds value: the core action, the when-to-use, the auth-dependent access, the null behavior, pagination, not_found handling, and the untrusted data warning. It is well-structured and front-loads the primary purpose, with no filler.

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?

The tool has moderate complexity (auth levels, pagination, untrusted data, no output schema). The description covers all critical aspects: the different data sets based on authentication, the null answer until seller responds, the pagination mechanism with limit and cursor, the not_found case, and the safety warning about untrusted fields. An agent can correctly invoke this tool and interpret responses without needing additional information.

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 only 33% (only cursor has a description). The description compensates by explaining the pagination parameters: 'Page with limit (≤ 50) and next_cursor.' It also implies that listing_id refers to the listing being queried. While listing_id is not explicitly described, its purpose is clear from context. The description adds meaningful semantics for limit and cursor that the schema lacks.

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 clearly states the action (read), the resource (questions and answers on a listing), and the ordering (newest first). It distinguishes itself from sibling tools like ask and answer by explicitly framing this as a read-before-ask operation. The phrase 'read it before you ask' directly contrasts with the ask sibling, making the purpose unambiguous.

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?

The description gives explicit usage guidance: 'read it before you ask; a public answer may already be there.' It also details what data is available with and without an API key, which tells the agent when the tool is sufficient (public/anonymous questions) and when it provides more (own private questions, seller's view). This clearly informs when to use this tool versus alternatives like ask or answer.

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