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

With no annotations, the description carries the full burden and does provide important behavioral guardrails: MATCHED_SINGLE is answerable, NEEDS_IDENTITY requires user choice, and NO_MATCH/UNAVAILABLE must not be guessed. However, it does not disclose whether the operation is read-only, how matching works, or what the response payload looks like.

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 description is compact and front-loaded, with no filler. The key safety constraint about not guessing is placed prominently. It is efficient, though perhaps too terse given the complexity of the 8-parameter 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?

There is no output schema and no annotation coverage, so the description must do more. It covers high-level match statuses but leaves unclear how to construct valid requests using the optional refinement fields, what the resolution response structure is, and how the tool behaves in ambiguous cases beyond NEEDS_IDENTITY. This is incomplete for a tool with 8 optional parameters.

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 only 13% (only 'vin' is described), so the description must compensate. It clarifies that the primary input can be either a VIN or a year/make/model combination, but it says nothing about trim, engine, drivetrain, or configuration_id, leaving half the parameters semantically undocumented.

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?

The description states a specific action ('Resolve') on a specific resource ('a VIN or year/make/model') and introduces match-status vocabulary. It is clearly distinct from the sibling get_vehicle_* tools, though it does not explicitly name them or state the difference.

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 'Resolve a VIN or year/make/model safely' implies this is an identity-resolution step before retrieving vehicle data, but the description does not explicitly say when to use this tool versus the get_vehicle_* siblings. The statuses imply a workflow (answer when MATCHED_SINGLE, ask when NEEDS_IDENTITY), but no direct exclusions or alternatives are given.

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