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

The annotations already mark the tool as readOnly/idempotent/non-destructive, and the description adds important non-obvious context: prepaid credit cost, no platform credentials, hosted official data, non-confidential nature, and LGPD responsibility. No contradiction was found, though returns behavior and failure/edge cases are not covering.

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 concise, front-loaded with the resource and action, and the legal/commercial context is given in short discrete sentences. There is some repetition of the word “oficial”, but it is minor and does not obscure the meaning.

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 tool with six parameters, zero schema coverage, and no output schema, the description over-delivers. An agent would still struggle to know what return data is expected, what the optional login/cert fields do, and what makes a request valid.

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 at all, and the description does not explain the meaning or formatting of placa, renavam, login_cpf, login_senha, pkcs12_cert, or pkcs12_pass. “Veículo” helps associate placa/renavam generally, but the agent would have to guess at credential-fields and value formats.

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 names the vehicle (“DETRAN ES”) and action (“consulta em fonte oficial”) and is unmistakably a read-only vehicle lookup. The siblings are platform utilities such as authenticate or marketplace, so this tool is clearly distinct.

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 useful context: it is an official no-costs-per-query citizen-level data query, not sensitive data, and the customer owns the LGPD purpose. However, it does not say the most explicit when to use this tool, when not to use it, or which alternatives are preferred.

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