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

With no annotations, the description carries the full burden of behavioral disclosure. It does disclose that the tool creates a payment, returns a URL and PIN, and uses a hosted checkout. However, it omits important behavioral context such as whether the customer is charged immediately, expiry behavior beyond optional parameters, idempotency, or required gateway configuration.

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 three short sentences with no filler. It front-loads the primary action and output, then adds useful context about supported payment methods. Every sentence earns its place.

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 14-parameter tool with no output schema, the description supplies the essential context: it creates a hosted payment link, returns a URL and PIN, and supports multiple payment methods. The lack of explicit flow guidance or edge-case handling is a minor gap because the schema thoroughly documents all parameters.

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 100%, and each parameter already has a meaningful description. The tool description adds no parameter-level semantics beyond confirming the hosted-checkout payment flow, so the baseline score of 3 is appropriate.

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 action ('Creates a Pay by Link / PINPAY payment') and the key outputs ('shareable payment URL and a PIN code'). This is specific enough to distinguish it from sibling tools like multibanco_create_reference or creditcard_create_payment.

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 hosted-checkout context implies this is the right tool for creating a payment link that supports multiple payment methods, but there is no explicit when-to-use guidance or comparison with sibling payment-creation tools. Selection relies on inference from the name and the phrase 'Pay by Link / PINPAY.'

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