create_setup_intent

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

The description states that the tool works via the gateway endpoint and returns a setupIntent.id that can serve as a paymentMethodNonce. It also warns 'No raw card data.' However, it lacks details about side effects, failure modes, or the distinction between creating and retrieving. For a tool with no annotations, the description carries full burden and could be more transparent.

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 consists of two sentences that are concise and front-loaded. The first sentence states the action, and the second provides usage context. Every sentence adds value, though it could be slightly more structured.

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?

Given the tool's role in a payment flow with only 2 parameters and no output schema, the description covers purpose and usage. However, it does not explain the 'create or retrieve' behavior in detail or specify the return structure, leaving some gaps.

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 input schema has 100% coverage with descriptions for both parameters ('Company gateway ID (required)', 'Customer ID (required)'). The description does not add extra parameter-specific details beyond the schema, so it meets the baseline of 3.

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 ('Create or retrieve a setup intent') and the resource ('via the gateway endpoint'). It distinguishes its purpose by noting it's part of a 'gateway-agnostic payment method flow' and references a sibling tool ('create_customer_payment_method'). However, the 'or retrieve' phrasing introduces some ambiguity about whether it always creates or can retrieve an existing one.

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 states when to use this tool ('Use only as part of a gateway-agnostic payment method flow') and provides a concrete next step ('the returned setupIntent.id can be used as paymentMethodNonce for create_customer_payment_method'). It does not explicitly state when not to use, but the context is clear enough.

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