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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered upstream. The description adds a useful, non-obvious behavior: a per-call cost of $0.002, plus the field shape returned. It does not mention pagination, result caps, or coverage limits of the CPSC dataset, which matter for an open-world source.

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, front-loaded with the data shape and ending with the decision context, so it is easy to scan. The inline field enumeration is dense but earns its place given there is no output schema.

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, describing the return structure (counts, unit totals, by-country and by-year breakouts, item fields) is necessary and done well. Remaining gaps are the semantics of `since`/`limit` defaults and any ordering or truncation behavior for the items array.

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 67% and the description reinforces the required parameter's meaning (product keyword) and implies the returned grouping dimensions. It adds little on `since` or `limit` beyond what the schema states, but with the schema already documenting most fields this is a modest gap only.

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: CPSC recalls looked up by product keyword, and enumerates the aggregate and per-item fields returned. An agent can distinguish it immediately from nearby siblings like product_brief or import_trends, which cover different datasets.

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 explicit usage context: check CPSC recalls for a product category (units, hazards, origin, Amazon sales) before sourcing or selling. It stops short of naming an alternative tool or a when-not-to-use condition, so it is clear but not fully routing.

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