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

Annotations already declare the tool as read-only, idempotent, and non-destructive. The description adds valuable behavioral context beyond these hints: it discloses the payment model (pay per query), the public nature of the data, the lack of credentials, and the LGPD responsibility of the client as data controller. This provides a clear operational and compliance picture without contradicting the annotations.

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 concise and well-structured. It leads with the primary purpose, then adds essential operational and legal context in a few sentences. Every sentence earns its place, and there is no redundant or filler content.

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 absence of an output schema and the 0% parameter description coverage, the description should provide more detail on expected inputs and outputs. It explains the high-level context and legal responsibilities, but it does not describe what the response contains or how to properly fill all parameters. This leaves gaps that an agent would need to resolve through inference or trial, making the tool under-documented for its complexity.

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?

The schema has 0% description coverage on parameters, so the description must compensate. It mentions 'a partir do CPF ou CNPJ', which gives a clue that one of these fields identifies the entity, but it does not explain the format, semantics, or purpose of the required fields 'ie' and 'Uf', nor the optional 'completo' flag. The description also implies that only CPF or CNPJ is needed, while the schema requires both, creating confusion for the agent.

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 function: to issue a federal Certidão Negativa de Débitos (CND) for an individual or company using CPF or CNPJ. The verb 'Emite' is specific, the resource is precisely identified, and the scope is unambiguous. It uniquely distinguishes itself from sibling tools, none of which perform similar certificate-issuing functions.

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 provides clear contextual guidance: it states the tool is hosted on the platform, requires no credentials, and charges per query with prepaid credit. It also clarifies that the data accessed is public, which sets expectations for legitimate use. However, it does not explicitly mention when not to use the tool or name alternative approaches, though no sibling tools offer a comparable function.

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