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

readOnlyHint=true already declares this a safe read, so the bar is lower. The description adds provenance ('openFDA device/recall endpoint') and the shape of returned records, but says nothing about rate limits, API-key behavior, or pagination ceilings that a search client would care about.

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 compact clauses, front-loaded with the verb and resource, with no redundant restatement of the title. The trailing endpoint fragment is terse but earns its place as provenance.

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 read-only search tool with no output schema, the description usefully enumerates the returned fields in place of a return-value contract, and the schema fully covers inputs. Only rate-limit and pagination caveats are absent, which is a minor gap.

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% with four fully documented parameters, including Lucene syntax and range examples. The description adds no parameter-level meaning beyond the schema, so the baseline 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+resource ('Search medical device recalls') and enumerates the content surfaced (reason, recalling firm, classification, product code, status). The 'device' qualifier implicitly separates it from search_drug_recalls and search_food_recalls, but no sibling is named 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?

No when-to-use, when-not-to-use, or alternative routing is provided. It never mentions openfda_query or count as complementary tools, nor the conditions for paginating with skip/limit. Usage is left entirely to inference from the name.

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