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

Since annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, the description doesn't need to restate safety. It adds value by specifying the exact document type (CNDT) and the accepted identifiers (CNPJ or CPF), which tells the agent the nature of the operation and what parameters to expect. There's 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 a single, concise sentence that states the core purpose and parameters. It is efficiently front-loaded with the tool's function and required inputs, with no redundant or filler content.

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?

Given that the tool is a read-only lookup with rich annotations (readOnly, idempotent, non-destructive) and no output schema, the description's brevity is somewhat acceptable. However, it doesn't explain additional context like whether CPF and CNPJ are mutually exclusive, or what the response contains (e.g., certificate status). The lack of parameter format and usage details makes it minimally viable but not fully complete.

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 provides only 'cpf' and 'cnpj' as string types with no descriptions, and schema description coverage is 0%, so the description must compensate. The description does not clarify the format (e.g., with or without punctuation), or explain that either parameter is optional or mutually exclusive. This is a significant gap for parameter understanding.

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: obtaining a CNDT (Certidão Negativa de Débitos Trabalhistas) using either CNPJ or CPF. It identifies the specific resource (labor debt clearance certificate) and the required input types, which is clear and distinguishes it from other consultation tools in the sibling list, though it doesn't explicitly name alternatives.

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 implicitly tells users when to use this tool: to obtain a CNDT for a company (CNPJ) or individual (CPF). It does not explicitly state when not to use it or mention alternatives, but the context of sibling tools (e.g., consultas_cpf for general CPF checks) implies this is specifically for labor clearance certificates. Overall, guidance is adequate but not explicit.

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