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

Annotations declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, and the description does not contradict these. However, the description focuses on legal and commercial aspects (LGPD, payment, data controller) rather than behavioral characteristics like what the tool returns, how it handles errors, or rate limits. It adds some context about data source (official Brazilian sources) and non-confidentiality, but that is not sufficient.

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 paragraph of moderate length but is not front-loaded with the core action. It mixes legal disclaimer, payment details, and data privacy information. Every sentence is not earning its place; for example, 'não é dado sigiloso' and 'O cliente é o controlador dos dados' are legal boilerplate that could be omitted. It is not concise in terms of clarity.

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 tool has a simple schema (one required parameter) and no output schema, the description is insufficiently complete. It does not explain what query results will contain, how to interpret the output, or any specific details about the consultation process. The description emphasizes legal and payment aspects but omits the essential functional details that an agent needs to correctly invoke the tool and interpret its response.

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% for the single parameter 'placa'. The description does not describe what 'placa' means beyond the context of 'veículos tanque' (tank vehicles), and it does not specify format (e.g., license plate format, required pattern). The description mentions 'consulta' and 'placa' is implied, but the description does not add any parameter semantics beyond the schema's name. Given the low coverage, the description should compensate but does not.

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 does not use a clear verb+resource pattern. It mentions 'INMETRO Instrumentos: Veículos Tanque, consulta em fonte oficial' but lacks a specific action like 'Consultar dados de...' It does not distinguish from sibling tools (all are generic platform tools, none similar). The name implies 'consultar' but the description is more about legal/business context than the tool's function.

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 on when to use this tool versus alternatives. It mentions 'pague por consulta' and 'sem credenciais' but these are operational constraints, not usage context. It does not explain scenarios where this tool is appropriate, nor does it mention alternatives. The sibling tools are unrelated, but no explicit usage guidance is given.

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