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

No annotations are supplied, so the description carries the full burden, and it does a solid job: it discloses the per-plan price, that errors are not charged, that empty/sem_certidao/nao_contribuinte results still count as a query, that the call is not covered by free queries, and that the call is blocked without confirmo_custo. What it omits is the operational profile: timeouts, latency, partial-failure behavior beyond the complete flag, and whether results are cached.

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?

It is dense but front-loaded: purpose and scope come first, then the return semantics of the complete flag, then billing rules. The price tiers are long but each clause carries billing information the agent needs in order to warn the user before spending balance.

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 multi-state, billable lookup with an output schema, the description covers what the schema does not: the meaning of complete=false and the warning that absence does not prove nonexistence, plus the full cost/confirmation model. Nothing needed to call it safely is 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 coverage is 100%, so the schema already documents each parameter, including the 'informe só um documento' constraint echoed in the description. The description adds the cost-plane meaning of the cost confirmation, but adds little else beyond the schema. Baseline 3 is the right level.

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 gives a specific verb and resource ("Procura inscrições estaduais"), an explicit scope ("nos 27 estados numa chamada"), the accepted identifiers (CPF, CNPJ or IE) and the key differentiator from the sibling consultar_ie: no UF required. An agent can tell immediately this is the national lookup rather than the state-scoped one.

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 context is clear: use it when the state is unknown and you want one call for all 27 states, and the cost-confirmation gate (confirmo_custo must be true only after the user accepts the cost) is spelled out. It never explicitly names consultar_ie as the alternative when the UF is known, so the routing is implied rather than stated.

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