Ficha completa de uma empresa pelo CNPJ (14 dígitos): razão social, atividade, endereço, porte, telefone, site e Instagram.
| Name | Required | Description | Default |
|---|---|---|---|
| cnpj | Yes | CNPJ com ou sem pontuação | |
| verificar | No | Conferir a situação cadastral ao vivo na Receita (padrão: true). Também acha CNPJs baixados/inaptos fora da base. |
Changes observed during successful MCP inspections.
Input schema / properties / verificarAdded value: +{
+ "description": "Conferir a situação cadastral ao vivo na Receita (padrão: true). Também acha CNPJs baixados/inaptos fora da base.",
+ "type": "boolean"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden: it implies a read-only lookup and lists the data returned, which is useful. However, it omits the live-Receita lookup behavior and its cost/latency implications (that only surfaces via the schema's 'verificar' param) and says nothing about error cases for invalid or unknown CNPJs.
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?
A single front-loaded sentence with the resource first and the return payload listed after; no filler or redundancy.
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?
For a simple two-parameter read tool with full schema coverage and no output schema, listing the returned fields largely substitutes for a return-value section. The main remaining gap is that the overlap with the sibling tool buscar_empresa is never addressed.
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 100%, so both parameters are already documented, and the description only reinforces the CNPJ identifier. Baseline 3 applies since the schema, not the description, explains 'verificar' and its default.
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?
States a specific verb+resource (fetch full company record by CNPJ) and enumerates the returned fields (razão social, atividade, endereço, porte, telefone, site, Instagram), so the agent knows exactly what comes back. It does not distinguish the tool from the sibling buscar_empresa, leaving the reader unsure which lookup to pick.
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?
No statement of when to use this versus buscar_empresa, which appears to be the alternative lookup tool. The only usage constraint ('14 dígitos') is a format rule, not a selection guideline.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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