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

Annotations already declare readOnly, idempotent and non-destructive, so the safety profile is covered. The description adds genuinely non-structural context: the data source (NHTSA ODI), the caveat that the account is the owner's own and unverified by NHTSA, and a 1-credit cost. It does not cover behaviour on an invalid or missing ODI number, which keeps it off 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?

The purpose and lookup key are front-loaded, the returned fields follow, and the audience/source/cost notes are appended as short fragments. There is no redundant or filler wording.

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 compensates by enumerating the returned fields (vehicle, components, crash/fire, injuries and deaths, dates, partial VIN, owner narrative). For a single-parameter read tool this is nearly complete; only error behaviour on unknown ODI numbers is unaddressed.

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 odinumber parameter is fully documented in the schema, including an example. The description adds only the restatement 'by its ODI number' and no format or range detail beyond what the schema supplies, so the 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 and resource ('Read one NHTSA owner safety complaint') plus the lookup key ('by its ODI number') and enumerates the returned fields. It also names the sibling tool vehicle_complaints as the discovery path, so an agent can distinguish it immediately.

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?

The phrase 'following up a complaint found with vehicle_complaints' establishes the order of operations and the intended audience. It stops short of stating when not to use it or what to do if the ODI number is unknown, so it is clear context without explicit exclusions.

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