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

Adds a lot beyond the thin annotations: dedup behavior when the CNPJ already exists, precedence of user-supplied fields over the registry lookup, and that the situacao cadastral appears in the response with a warning if not ATIVA. Does not cover auth/account requirement or any rate/limit behavior, so not a 5.

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?

Front-loads the shortcut and the key behavior in a compact block of sentences; every clause carries information. Slightly dense with stacked clauses, but 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?

Covers the workflow, dedup, precedence and response signal well, which matters for a create tool with no output schema. However, for a 17-parameter tool it leaves most parameters undescribed, so it is adequate but with a clear gap.

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?

With 17 params and 0% schema description coverage, the description carries the full burden, yet it explains only the main ones (documento/CNPJ, razao_social, nome_fantasia, endereco, email, telefone). It leaves cep, bairro, cidade, estado, complemento, endereco_numero, observacao, inscricao_estadual, codigo_cliente_integracao, account, and the 'tipo' enum (fornecedor/cliente/ambos) unexplained, with no format hints such as CNPJ formatting.

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 plus resource ('cadastra um FORNECEDOR (ou cliente) na Omie a partir do CNPJ'), lists the fields it auto-populates from the Receita Federal query, and names the sibling to use for CPF (omie_create_customer). An agent can distinguish it from omie_create_customer without opening either schema.

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?

Explicit when-to-use (CNPJ, no manual typing) and an explicit exclusion with the alternative ('Só CNPJ: pra CPF use omie_create_customer'). It also states the de-duplication condition up front.

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