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

The description adds substantial behavioral context beyond the annotations. It discloses that the tool is hosted on the platform, does not require platform credentials, has a per-query cost with prepaid credit, queries official Brazilian public sources, and emphasizes LGPD compliance with the client as data controller. This is highly transparent and complements the readOnlyHint and idempotentHint annotations.

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, with three sentences covering purpose, hosting/payment model, and compliance. The most important information is front-loaded, and every sentence adds value. Slightly verbose legal wording ('LGPD') is acceptable given its relevance, but it remains focused.

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?

The description covers purpose, pricing, and compliance but omits details about the response format, error handling, or how to interpret the DUA data. Given the tool's simplicity and lack of output schema, this is adequate but not exhaustive. It explains the 'why' (compliance) but not the full operational context.

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 description provides no explanation of the parameters (placa, renavam, login_cpf, etc.) and does not clarify their format or purpose. With 0% schema description coverage, the description should compensate but does not. The mention of 'sem credenciais da plataforma' could confuse users about the login_cpf/pkcs12 fields, as it does not clarify how these are used.

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's purpose: querying/emitting a DUA (Documento Único de Arrecadação) from DETRAN ES via an official source. The verb 'consulta' and resource 'DUA' are specific. Although sibling tools are unrelated, the description distinguishes this tool by describing its domain (DETRAN ES) and function, making it clear what it does.

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 implies usage by explaining the tool is hosted on the platform, requires no platform credentials, and is paid per query with prepaid credits. However, it does not explicitly state when to use this tool versus alternatives or provide exclusion criteria. It gives context about the execution environment but lacks direct guidance on when to choose this tool.

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