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

Annotations already indicate read-only and idempotent behavior. The description adds significant context beyond that: no credentials needed, per-query prepaid credit, and LGPD responsibility, which are not captured in the 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 three sentences, each carrying essential information: purpose, hosting/pricing, and legal compliance. There is no wasted wording.

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 omits critical invocation details: the expected format for MESANO (e.g., MMYYYY) and the logic behind requiring both CPF and CNPJ simultaneously. While it provides legal and billing context, the ambiguity around required fields and optional 'completo' parameter makes the tool not fully self-sufficient.

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?

With 0% schema description coverage, the description must compensate. It hints at CPF/CNPJ for 'pessoa física ou jurídica' and MESANO for 'mês e ano de referência', but it does not explain the 'completo' boolean or clarify why both CNPJ and CPF are marked required in the schema. This leaves key parameters underspecified.

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 function: 'Detalhamento das operações de crédito... no SCR do Banco Central' by month and year for individuals or legal entities. This provides a specific verb and resource, distinguishing it from generic sibling tools like authenticate or connect.

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 clear context: hosted by the platform, prepaid billing, and a requirement for legal basis (e.g., risk analysis). It does not explicitly name alternatives, but there are no sibling tools performing this type of credit query, so the absence of exclusions is acceptable.

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