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

Annotations already declare readOnlyHint=true and idempotentHint=true. The description adds valuable operational details beyond that: payment via prepaid credit, absence of platform credentials, official-source nature, non-confidential data, and LGPD data-controller responsibility. No contradiction with 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 and front-loads the core purpose. It is not overly long, though the LGPD legal boilerplate adds length without directly aiding tool invocation.

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, source, payment, credentials, and data governance. However, it omits parameter semantics (which identifier to provide) and return-value behavior, and there is no output schema to compensate. Adequate for a simple query tool, but gaps remain.

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%, and the description never mentions cpf/cnpj, their relationship (e.g., one required, mutually exclusive), or formatting. The parameter names are self-explanatory to Brazilian users, but the description does not compensate for the complete lack of schema-level meaning.

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 this tool queries a 'Certidão Negativa de Débitos' from 'Prefeitura MG Divinópolis' at an official source. The verb 'consulta' and specific resource distinguish it from generic sibling tools like authenticate or report_bug.

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 useful context: hosted by the platform, no platform credentials needed, prepaid credit per query. However, it does not explicitly state when to prefer this tool over alternatives or when not to use it, though the siblings are unrelated platform utilities.

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