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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the description doesn't need to repeat those. However, it adds no additional behavioral context—no return format, limitations, or authorization requirements. The one-liner is essentially the purpose, not behavioral disclosure beyond 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 in Portuguese, front-loaded with the essential information. No wasted words, but it is minimal and lacks structure to elaborate on details.

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?

With a single parameter and no output schema, the description is too sparse. It doesn't explain what the agent should expect as a return (e.g., certificate validity status) or any additional context like auth requirements. For a simple lookup, this may be enough for a human but leaves an AI agent guessing.

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 only adds 'por CNPJ', which merely restates the parameter name. No format (e.g., digits only, with/without punctuation) or constraints are given. Given the low schema coverage, the description should compensate but doesn't.

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 checks employer regularity with FGTS (CRF) by CNPJ. It uses a specific verb (Regularidade) and resource (FGTS) and distinguishes itself from sibling consultas_* tools that query other data (e.g., CPF, NF-e, Simples).

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 implies usage (to check FGTS regularity via CNPJ) but provides no explicit when-to-use, when-not-to-use, or alternative tools. Since there are many sibling consultas tools, guidance on selection would help, but it's not forbidden.

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