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

Annotations already signal read-only, idempotent, and non-destructive behavior. The description adds relevant context beyond that: prepaid cost-per-query, no secret data, LGPD responsibility, and the client as data controller. These extra disclosures make the tool's operational and legal behavior transparent.

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 relatively concise, front-loads the core purpose, and each sentence covers a distinct point: data source, platform/payment model, confidentiality, and legal responsibility. There is minor redundancy around 'official source,' but it is not bloated.

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?

Given the simple parameters and safe read-only annotations, this description provides enough operational and legal context for tool selection. It is missing explicit information about output structure or exactly which vehicle fields are returned, but the return does not have an output schema and the gap is mostly for the parameter semantics.

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 schema has no descriptions for the four parameters, and the description does not compensate for the 0% coverage. It does not explain the meaning, format, or required combination of placa, renavam, cpf, or cnpj beyond what the property names themselves already imply.

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 the tool performs vehicle consultations against official DETRAN TO sources ('Veículo, consulta em fonte oficial'). It identifies both the action and the resource, and the sibling tools are unrelated enough that the intended purpose is not ambiguous.

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 gives practical usage context: this is a paid, prepaid-credit lookup against official Brazilian sources, requires no platform credentials, and returns information that is public/non-confidential. It does not explicitly enumerate when-not-to-use cases or alternative tools, but the intended scenario is clear.

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