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

The description adds meaningful behavioral context beyond the read-only/idempotent annotations: it explains conditional PBEV data ('quando há match auditado'), conditional photos ('quando existirem'), the proprietary size-classification methodology, the default effect of the `resumida` flag, and scope exclusion of maintenance plans.

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 front-loaded with the main purpose and uses compact, information-dense phrases to enumerate output content and conditions. It remains focused and does not include irrelevant details.

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 simple, read-only lookup with three documented parameters and no output schema, the description is complete enough: it lists the return content categories, conditional data availability, default response mode, methodology caveat, and a scope exclusion. An agent can accurately decide when and how to call it.

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 for parameters is already 100%; the schema descriptions for ano, fipeId, and resumida already provide the core meaning. The tool description largely restates the resumida behavior rather than adding new parameter-level meaning beyond the schema.

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 states that the tool returns the technical data sheet for a version/model-year, including dimensions, engine, fuel consumption, PBEV-Inmetro seal when audited, size classification, and photos. It also distinguishes itself by explicitly saying it does not include the maintenance plan and by noting its own size-classification criterion rather than Inmetro's Annex D.

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 intended use is clear from the opening 'Ficha técnica de uma versão×ano-modelo' and the explicit exclusion of maintenance plans helps avoid using it for that need. However, it does not explicitly name alternative sibling tools or state a direct 'use X instead' comparison.

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