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

Annotations already establish readOnly/idempotent/open-world/non-destructive, and the description is fully consistent with them. It adds genuinely useful behavioral context beyond annotations: no auth required, US Consumer Product Safety Act public domain provenance, and 'unlimited free' access — effectively covering auth needs and rate limits that the annotations don't convey.

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 opening sentence is front-loaded with the verb, resource, and identifier options. The ~15-item enumeration of return fields is verbose and partly redundant given an output schema exists, but it is still useful for quick scanning, and the closing usage and auth statements each earn their place.

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 2-parameter, 0-required lookup with 100% schema coverage, rich annotations, and an output schema, the description covers everything an agent needs: purpose, both identifier pathways, the search-then-detail workflow, return content, and access policy. No meaningful gap remains for correct invocation.

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 100%: both recall_id and recall_number carry examples, format hints, and the exact 'at least one of' mutual-exclusion rule. The description's 'e.g. 26582' and the search-flow hint merely echo the schema, adding no new parameter meaning, so the high-coverage 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 ('Retrieve'), resource ('a single CPSC recall notice'), and the two accepted identifier forms (numeric RecallID or recall number string with example '26582'). The tool distinguishes itself from its siblings — cpsc.safety.search is positioned as the preceding list step, while by_manufacturer and recent are obviously different — so an agent can select it correctly without opening the schema.

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?

Provides explicit when-to-use guidance: 'Use after cpsc.safety.search to get complete details on a specific recall record,' naming the exact sibling to chain with and the sequencing. It lacks explicit when-not guidance for the other two siblings (by_manufacturer, recent), so it stops short of a full 5.

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