Definir forma de pagamento da assinatura

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

Annotations already indicate destructiveHint=true, so the agent knows it modifies state. The description adds that it enables recurring charges, which is useful context beyond annotations, but does not detail permissions or side effects.

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 short, front-loaded sentences in Portuguese. Every word serves a purpose: action, resource, purpose, and outcome. No redundant information.

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 explains the tool's role in a multi-step subscription flow. Given the complex schema and presence of an output schema, it provides adequate context. Could mention prerequisites like a valid subscription ID, but the required param 'id' covers that.

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% with detailed descriptions for each field, so the description's mention of 'forma de pagamento e os dados do cliente' adds minimal extra meaning beyond what the schema already provides.

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 uses a specific verb ('associa') and resource ('assinatura previamente criada'), clearly distinguishing it from sibling tools like 'define_pay_method' which is for one-time charges. It states the outcome: enable recurring charges.

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 explicitly says to use this tool to complete the second step after creating a subscription. It implies context but does not explicitly exclude alternatives or state prerequisites, leaving some room for ambiguity.

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