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

Annotations already cover the safety profile via readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the description does not need to restate that. It adds useful behavioral context by explaining that `section` restricts the response to one named section, including the exact accepted values. However, it does not disclose response format, error behavior, or data freshness, which a bare read-only lookup could reasonably mention.

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 a single dense sentence that front-loads the purpose ('Ficha técnica completa') before enumerating the data domains. The inline list of valid `section` values is necessary because the schema defines no enums, so it earns its place despite making the sentence somewhat long.

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?

This is a simple two-parameter read-only lookup, and the description adequately communicates the response content and the optional filtering behavior. The absence of an output schema is mitigated by the enumerated technical-spec domains, though exact return structure and validation behavior for invalid section names remain unspecified.

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?

The description adds meaningful detail for `section`, listing all valid values and explaining that it restricts the result to a single section, which the bare anyOf schema does not convey. However, `car_id`, the required parameter, is only identified by its name and type; with 0% schema description coverage, the required identifier deserves explicit semantic clarification.

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 clearly identifies the resource: a complete technical spec sheet (engine, power, torque, transmission, consumption, performance, dimensions, brakes, tires). It also introduces the optional `section` restriction, which helps distinguish this from broader vehicle-level tools. It does not explicitly contrast with sibling tools like get_listing_details or get_vehicle_by_id, but the content is specific enough that confusion is unlikely.

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 description provides no guidance about when to use this tool versus its siblings, such as get_listing_details or get_market_stats. It states what data is returned but not which scenarios call for this tool or which alternatives would be more appropriate.

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