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

With no annotations, the description carries the burden and does well: it discloses the returned content shape and the `found: false` negative-result semantics, which prevents the agent from treating an empty result as an error. It omits that this is a non-mutating lookup and says nothing about failure modes beyond not-found, keeping it short of a 5.

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, no filler. The positive result shape comes first and the edge case (`found: false`) is front-loaded into the second sentence where it is most likely to be read.

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?

There is no output schema, so the description justifiably describes return fields and the not-found indicator, which is exactly what an agent needs before calling. The only gap is that it does not describe the shape of a successful response wrapper beyond field contents, but for a one-parameter read tool this is close to sufficient.

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 parameter already has an example (`REC-006722`) and a source pointer, so the schema does the heavy lifting. The description adds nothing about the identifier beyond "that number", 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 and resource ("Return one recall notice") and immediately enumerates the payload (defect, hazard, owner action, contact), which distinguishes it from the sibling search_recalls that would return many. An agent can tell single-record retrieval apart from listing without inspecting either 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?

Usage context is clear but implicit: "one recall" plus the schema note that the number comes from `search_recalls` or a lookup match routes the agent correctly. It does not explicitly say "use this after search_recalls returns a recall number" or name lookup_vin as an alternative source, so the when-not guidance is absent.

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