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

Annotations already declare read-only, idempotent, and non-destructive behavior. The description adds valuable context: no authentication needed, pay-per-query billing, public data source, and LGPD compliance responsibility. It does not describe response format or error cases, but the safety profile is well covered by 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 front-loaded with the core purpose and each sentence adds relevant context (payment model, public access, LGPD). It is reasonably concise, though the legal disclaimer could be slightly tightened without losing 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?

Despite having annotations for safety, the tool has 3 parameters with 0% schema coverage and no output schema. The description omits input formatting, the meaning of Qsa and 'completo', and any details about the response. It covers the access model and legal context but leaves essential invocation details unaddressed.

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 clarify parameters. It only explains CNPJ and vaguely mentions 'quadro societário' for Qsa, but does not explain Qsa's expected value format, why it is required, or what the optional 'completo' boolean does. This is insufficient for reliable invocation.

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 uses a specific verb ('Consulta') and a clear resource ('dados cadastrais de uma empresa na Receita Federal'), explicitly naming CNPJ as the key input and mentioning the optional 'quadro societário'. This makes the tool's purpose unambiguous and distinguishes 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 operational context: it is hosted by the platform, requires no credentials, charges prepaid credits per query, and is limited to publicly accessible data. It does not explicitly name alternatives or exclusion cases, but no similar sibling tool exists, and the prerequisites for use are clear.

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