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

Annotations already declare readOnlyHint and idempotentHint, so the description adds little on safety. It does disclose the cost model ('pague por consulta') and LGPD responsibility, but it does not mention response format, pagination, or error behavior.

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 three sentences long and begins with the core purpose, followed by payment and compliance details. It is concise and readable, though the legal sentence occupies space that could have clarified parameters.

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?

With 8 parameters and no output schema, the description is incomplete. It explains the tool's high-level purpose and some context, but not how to invoke it correctly or what the parameters mean, making it insufficient for a complex 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?

The schema has 8 parameters with 0% description coverage, and the description does not explain any of them (e.g., 'pagina', 'data_inicial', 'login_cpf'). This leaves the agent guessing about parameter meaning, and the description fails to compensate.

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 it is a 'consulta' (query) for 'Notas Emitidas' (issued NFS-e) from 'Receita Federal', a specific verb and resource. It distinguishes itself from sibling tools, which are unrelated (authenticate, connect, etc.).

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 context about payment ('pague por consulta com crédito pré-pago') and no platform credentials ('sem credenciais da plataforma'), but it does not explicitly state when to use this tool over alternatives or provide exclusion criteria. Sibling tools are unrelated, so no direct alternative is addressed.

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