consultar_cnpj

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

No annotations exist, so the description carries the full burden. It usefully discloses the data provenance (Minha Receita primary, OpenCNPJ and CNPJá as fallback) and that the response flags the source used, which is real behavioral value. It does not, however, cover rate limits, caching, or what happens on an unknown/invalid CNPJ, which matters for a tool aggregating free public APIs.

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?

Compact and front-loaded: the returned payload is described first, then the source/fallback behavior. Every clause earns its place and there is no 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?

With no output schema, the description compensates by enumerating returned fields and noting the source indicator. That covers the essentials for a single-parameter lookup tool; only error/failure semantics are missing.

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% and the single parameter already documents that masked or unmasked 14-digit input is accepted. The description adds no format, validation, or normalization detail beyond the schema, so the baseline 3 applies.

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 concrete verb+resource ('Ficha completa de um CNPJ') and enumerates the returned fields (razão social, situação, endereço, CNAEs, Simples/MEI, sócios), so the agent knows exactly what it gets. It is implicitly distinct from siblings like buscar_empresa_por_nome or socios_em_comum, but it never names an alternative, so differentiation is left to the agent.

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?

Usage is only implied: the tool takes a CNPJ, so an agent infers it should be used when a CNPJ is in hand and name/socio/address lookups should use the other tools. There is no explicit when-to-use statement, no prerequisite (e.g. valid CNPJ required), and no named alternative for the case where the agent lacks a CNPJ.

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