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

Adds materially beyond the annotations: it discloses that the call only creates a preview plus a single-use link, that it "issues, charges and sends nothing," and that identifiers (CPF/CNPJ/RG) are refused and must be added on the site. That reconciles cleanly with destructiveHint=false and readOnlyHint=false and clarifies why each call is a fresh draft (idempotentHint=false).

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 core action and its limits are front-loaded in the first two sentences, and the long exclusion clause is necessary routing information rather than filler. The final formatting sentence is dense and partially duplicates the schema, which keeps it from a 5.

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?

For a non-destructive draft-creation tool with an output schema and full parameter documentation, everything an agent needs is present: what is produced, what is not done, what input formats are accepted, and which adjacent use cases belong elsewhere. No material gap remains.

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 100%, so tipo and the open-ended campos object are already documented, including the value formats. The description still adds real semantics: which type identifiers exist, that campos is keyed by the type's field ids from list_document_types, and the hard constraint that CPF/CNPJ/RG values are rejected.

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?

Opens with a specific verb and resource set ("Drafts a Brazilian payment receipt, rent receipt, service quote or service order on Reciba") and states the output ("returns a single-use link"). The enumerated document types map directly onto the tipo values, so an agent can tell exactly what this tool produces versus the listing/verification siblings.

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?

Gives explicit when-to-use ("documents the person issues about their own service, sale or rental") and explicit when-not (nota fiscal, receipts a third party must issue such as a dentist or landlord, Receita Saúde receipts, pricing advice). It also states the division of labor: the tool prepares, the person reviews and issues from their own account.

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