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

Beyond the readOnly/idempotent annotations, the description adds meaningful behavioral context: no credentials needed, prepaid credit per consultation, public-access nature of the data, and the client's role as data controller under LGPD. These details help the agent set user expectations and understand compliance implications.

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: first sentence states the core purpose, the second covers payment/hosting, and the third addresses public access and legal responsibility. Every sentence earns its place with no filler or repetition.

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?

The description covers purpose, cost, access class, and legal context well, which is strong for a simple public lookup. However, with no output schema, the description should provide more about the expected return ('completo' behavior, response format, or certificate details), and the CPF/CNPJ requirement mismatch further harms completeness.

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 0%, so the description must compensate, but it only partially does. It clarifies that Cpf and Cnpj are person/company identifiers, yet it says 'ou' (or) while the schema lists both as required. The optional 'completo' parameter is not explained at all, leaving a semantic gap and a potential contradiction.

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 specific action ('Emite') and resource ('certificado de regularidade ambiental') plus the target audience (pessoa ou empresa a partir do CPF ou CNPJ). This distinguishes the tool from the unrelated sibling tools and makes the purpose immediately obvious.

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 useful selection context: it is hosted by the platform, requires no credentials, is paid per query, and consults only public official data. It explicitly excludes private or confidential data and mentions LGPD responsibility. It does not name alternative tools, but no direct sibling competitor exists, so the guidance is adequate.

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