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

Annotations cover the safety profile (readOnlyHint, openWorldHint), and the description adds substantial context beyond them: API-key auth requirement, ordering, the meaning of status (verified vs pending settlement), review_status semantics (can_rate/rated/not_verified, mine vs theirs), the shared-human review-count-0 rule with its 'why', and the _untrusted marking of seller-authored fields.

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 core purpose before the dense field semantics. It is long and parenthetical-heavy (backticks, semicolons), which hurts readability, but essentially every clause carries substantive information about return values or the review flow.

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 must carry the return-value burden, and it does so thoroughly: listing, seller profile id/name, transaction hash, amount, status, and review_status are all explained. Nothing an agent needs to call and interpret this tool 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% and the single `limit` param is fully documented in the schema, so the schema does the heavy lifting. The description's 'newest first' merely restates the schema's ordering note and adds no syntax or range detail.

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?

Opens with a specific verb+resource ('What you bought'), states the ordering ('newest first'), and enumerates the returned fields. The review-flow guidance ('Use the purchase_id with review()') implicitly separates it from siblings like mySales, myReviews, and getReviews.

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 context: needs an API key, newest-first ordering, and routes the agent to review() via purchase_id. It does not explicitly state when to prefer this over mySales or getReviews, so it lacks hard exclusions, but the operational context is strong.

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