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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered; the description adds real extra context by disclosing the $0.004 USDC per-call x402 cost and the fields returned (hazard, remedy, dates). It omits rate limits, failure modes, and payment-failure behavior, which would round it out for a paid external call.

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?

Two sentences, zero padding: capability and source coverage first, cost second. Everything is front-loaded and each clause carries distinct information.

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 no output schema, the description usefully names the returned fields and the covered datasets, and it flags the payment model. The remaining gap is that all six parameters are optional with no stated default or behavior for an unfiltered call.

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 description coverage is only 17% (just the 'type' enum string), so the description carries most of the burden and does so for five of six parameters by mapping q to product name and make/model/year to vehicle lookups, plus the implicit type taxonomy. The limit parameter remains undefined in both places.

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 domain (product safety recalls) and enumerates the three underlying sources with their lookup keys: CPSC consumer products, FDA enforcement for food/drugs, NHTSA for vehicles. This clearly separates it from near-neighbors like hazards, drug, and nutrition in the sibling list.

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 concrete routing guidance: query by product name for consumer/food/drug recalls, by make/model/year for vehicles, so the agent knows which parameter set to use per data source. It does not state when to prefer this over siblings (e.g., hazards or drug) or what happens when no filters are supplied.

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