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

Annotations include destructiveHint=true, and the description adds 'Irreversível' (irreversible) and mentions bulk support and optional field for cancel_pending_invoices. No contradiction.

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?

Two sentences with no fluff. The first sentence is front-loaded with core purpose and key details; the second adds bulk support efficiently.

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?

Although the description covers core functionality and irreversible nature, it lacks information about return values and side effects beyond irreversibility. For a tool with no output schema, this is a notable omission.

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?

With 0% schema coverage, the description must compensate. It explains subscription_id (required), data (optional with cancel_pending_invoices), and subscription_ids (bulk). However, it does not explain the account parameter, leaving a 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 verb 'Cancela' (cancel), resource 'assinatura' (subscription), platform 'Pagar.me V5', required parameter 'subscription_id', optional data field, and that it is irreversible. It distinguishes from siblings like pagarme_charges_cancel by targeting subscriptions.

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 specifies when to use this tool (to cancel a subscription) and mentions required and optional parameters, including bulk support. However, it does not explicitly contrast with alternative tools like pagarme_charges_cancel or provide 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.