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

Beyond the readOnly and idempotent annotations, the description discloses the hosted nature, lack of credentials, payment model, external data sources (bureaus), and regulatory responsibility (LGPD). This gives the agent a complete picture of what happens when the tool is invoked.

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 bit long but front-loaded with the primary purpose and each subsequent sentence adds valuable context (payment, legal, data sources). No sentence is redundant, though the LGPD detail could be condensed.

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, source, auth, and legal aspects, but it lacks any explanation of the return value or output format. For a credit analysis tool that suggests a limit, the agent would benefit from knowing what the response contains. The 'completo' parameter is also left undefined, so the description isn't complete enough for correct invocation.

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%, so the description must fully explain parameters. The CNPJ is mentioned in the purpose, but the 'completo' boolean parameter is entirely unexplained. The agent cannot know whether to set it true/false or what effect it has, leaving a significant gap.

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 performs a complete credit analysis of a company using CNPJ, including a credit limit suggestion. This specific verb+resource combination distinguishes it from the unrelated sibling tools and leaves no doubt about its function.

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 key usage context: no credentials required, pay-per-query with prepaid credits, and mandatory legal basis (LGPD). It doesn't explicitly compare to alternatives, but with generic siblings this is sufficient guidance.

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