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

Annotations already indicate readOnlyHint=true and destructiveHint=false, so the tool is safe. The description adds context about the data source being official and non-confidential, plus a note on LGPD compliance for the client as data controller. These are valuable behavioral and legal context beyond the annotations, though it doesn't disclose specifics about authentication or potential failures.

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 one paragraph but contains several distinct pieces of information: purpose, source, hosting, payment, data confidentiality, and LGPD compliance. It is concise and front-loaded with the core purpose. However, it could be better structured with separate sentences for clarity, but it is not unnecessarily long.

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?

Given the complexity (7 parameters, no schema descriptions, no output schema), the description is incomplete. It does not explain the return format, how to provide authentication credentials (login_cpf, etc.), or which parameter combination is required (CPF vs CNPJ). The watchdog hints are present, but the tool's behavior in terms of outputs and error handling is not documented.

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% (the schema has no descriptions for the parameters). The description only mentions the general consultation without explaining any parameter semantics. It does not provide details on how to use 'ie', 'cpf', 'cnpj', or the authentication-related parameters. Since there are 7 parameters and no schema descriptions, the description should compensate, but it does not.

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's purpose: querying the SEFAZ PE Certidão de Regularidade Fiscal from an official source. It specifies the resource (SEFAZ PE) and the action (consultar). However, it does not explicitly differentiate from siblings, but there are no direct sibling tools for this specific query, so it stands out sufficiently.

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 states that it consults official Brazilian sources and is not confidential data, but it does not define clear scenarios for when to use this tool versus alternatives. It mentions payment per consultation with prepaid credit, which implies a usage condition, but lacks explicit guidance on when to prefer this tool over others.

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