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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds meaningful behavioral context: no credentials required, prepaid credit model, public access legal basis, and LGPD controller responsibility. This goes beyond annotations and clarifies important operational and legal traits.

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 organized into four sentences, each delivering useful information: purpose, hosting/payment, public status, and legal responsibility. It is slightly dense but not bloated; every sentence earns its place.

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?

No output schema exists, so the description should hint at the return content; it does not. Parameter requirements are ambiguous, and the 'completo' field is unexplained. However, the description covers access, payment, and legal context adequately for a read-only consultation tool.

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 0%, so the description must compensate. It mentions 'CPF ou CNPJ' but the schema requires both Cpf and Cnpj as separate required fields, creating ambiguity about whether one or both must be provided. The 'completo' parameter is never explained. No formats, exclusivity, or usage semantics are given.

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 'Histórico dos veículos vinculados a um CPF ou CNPJ em âmbito nacional' which is a specific verb+resource+scope. It clearly identifies the tool's function and differentiates it from unrelated sibling tools.

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 clear usage context: hosted on the platform, no credentials needed, pay per query with prepaid credit, and that it accesses public official data. It doesn't explicitly name alternatives or exclusions, but the context is sufficient given no similar sibling tools exist.

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