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

Annotations are all false, so the description carries the burden. It adds meaningful context: no cancellation fee, only unpaid boletos can be canceled, and bulk execution is supported. This goes beyond the structured fields.

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 compact and front-loaded: the main action is stated first, followed by fee information and bulk support. No unnecessary words or redundancy.

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 cancel operation with no output schema, the description covers purpose, condition (unpaid), fee, and bulk mode. It lacks return/error details, but the core is well enough specified.

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 description explains transaction_id as the key and transaction_ids for batch, but it does not mention the account parameter. With 0% schema coverage, it partially compensates but leaves one parameter undocumented.

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 cancels an unpaid boleto using transaction_id, specifying the exact verb and resource. The sibling paghiper_cancel_pix further distinguishes it as boleto-specific.

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?

It provides clear context by limiting cancellation to unpaid boletos and mentions bulk support via transaction_ids. It doesn't explicitly name alternatives, but the 'ainda não pago' condition gives a clear when-to-use guidance.

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