create_customer_payment_method

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

No annotations are provided, so the description carries the full burden. It discloses that the tool is gateway-agnostic, does not accept raw card data, and requires a single-use token. It doesn't discuss mutation side effects or return format, but it is transparent about the data handling and integration path.

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 sentences, front-loaded with the purpose. The second sentence lists required fields, and the third explains the token workflow. While efficient, there is minor redundancy (e.g., 'Gateway-agnostic:' repeats info from schema). Still, it is well-structured for quick parsing.

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 covers purpose, workflow, and parameters. However, with no output schema and no mention of return values (e.g., created payment method object or ID), the agent lacks information about the tool's output. For a creation action, this is a notable gap, lowering completeness.

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%, baseline 3. The description adds value by explaining the workflow for paymentMethodNonce, specifying that billingAddress requires countryCode, street1, city, state, zip (with street2 optional), and clarifying type values ('card or ach'). This goes beyond the schema field descriptions.

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's purpose: 'Create a payment method for a customer.' It specifies gateway-agnostic nature and enumerates required fields. This differentiates it from sibling tools like update_customer_payment_method, delete_customer_payment_method, and get_customer_payment_method.

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 provides a clear workflow: obtain gateway client credential via get_client_token, use a payment integration to produce a paymentMethodNonce, then call this tool. It does not explicitly state when not to use this tool or mention alternatives, but the prerequisites and process are well explained.

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