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

Annotations already declare read-only, idempotent, and non-destructive behavior. The description adds valuable context: hosting on the platform without platform credentials, per-query cost with prepaid credit, the public nature of data, and LGPD responsibilities for the client. It does not contradict annotations and enriches behavioral understanding.

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 a single, well-structured sentence that front-loads the core purpose (SEFAZ: CCC query from official source) before adding practical and legal details. Every clause adds value, with no redundancy or unnecessary 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 tool has 8 parameters and no output schema, the description is insufficient. It does not explain parameter formats, valid values, or how to structure queries. The high-level business context is present, but essential technical details are missing, leaving the agent uncertain about how to properly invoke the tool.

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%, and the description offers no information about any of the 8 parameters (e.g., ie, cpf, cnpj, login_cpf, etc.). It only mentions a query without clarifying which parameters are needed beyond the required 'uf'. The description fails to compensate for the schema's lack of documentation.

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 identifies the tool as a query for the Centralized Taxpayer Registry (CCC) from SEFAZ, specifying a particular resource and action. It distinguishes itself from sibling tools by naming the specific official source and nature of the data, though siblings are largely unrelated.

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 context about payment and data legitimacy but does not explicitly state when to use this tool versus alternatives or what conditions apply. It implies the tool is for accessing public official data but lacks explicit 'when not to use' guidance.

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