validar_cpf

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions that the tool returns the reason for invalidity, but it does not describe the accepted input format, the output structure for valid CPFs, or whether the operation is purely local and read-only. This leaves significant ambiguity for an agent.

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 main function and a key behavioral detail. It is front-loaded and free of unnecessary filler.

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 the absence of annotations, an output schema, and parameter descriptions, the description should provide more context about input format and return behavior. It only partially explains the output (invalidity reason) and omits details about valid inputs and the structure of the returned data, making it incomplete for an agent to invoke the tool confidently.

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 input schema has one parameter 'cpf' with no description, and the tool description does not elaborate on the parameter's format, constraints, or examples. The description only repeats the term 'CPF' from the parameter name, adding no meaning beyond the schema.

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 action 'Valida' (validates) and the object 'um CPF' (a CPF), adding the specific behavior of returning the reason for invalidity. This distinguishes it from sibling tools like 'gerar_cpf' and 'validar_cnpj'.

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 does not explicitly mention when to use this tool versus alternatives such as 'validar_cnpj' or 'gerar_cpf'. The use case is implied by the tool's name and description, but no explicit guidance or conditions are provided.

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