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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds meaningful context annotations do not: a pay-per-call cost model ($0.01 USDC via x402) and the fact that billing occurs only on success, which materially affects invocation decisions.

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?

One tightly packed sentence plus a short pricing sentence, with the retrieval scope front-loaded before the cost note. Every clause carries information and there is 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?

For a one-parameter read-only search with full schema coverage and annotations covering the safety profile, the definition is nearly sufficient. The remaining gap is that with no output schema, the description does not sketch what a returned recall record contains, which would help an agent interpret results.

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 'q' parameter is fully documented with examples in the schema itself. The description's phrase 'product or brand' restates the schema rather than adding syntax, format, or matching-behavior detail, so the baseline of 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 and resource ('Search recalls for a product or brand') and enumerates the exact data sources covered (US CPSC consumer product recalls plus FDA enforcement reports for food, drugs and medical devices). This distinguishes it from domain-specific siblings like check_motor_carrier_safety and verify_healthcare_provider, though it never names a sibling explicitly.

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 enumerated source domains imply scope (consumer products, food, drugs, medical devices), letting an agent infer when this tool applies versus the other check_* siblings. However, there is no explicit when-to-use guidance, no exclusions, and no routing to alternatives for adjacent questions.

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