Create Credit Pack Checkout

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

Annotations already indicate idempotentHint=false and openWorldHint=true, so the description does not need to restate those traits. It adds value by identifying Stripe as the external processor and clarifying that the result is a checkout link rather than a direct charge, but it does not disclose additional behavioral details such as link expiration or repeated-call 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?

One sentence with no filler, front-loading the core purpose and the key differentiator ('one-time extra credits'). Every word contributes to selecting or invoking the tool correctly.

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 simple two-parameter tool with enums, a full output schema, and annotations covering idempotency and open-world behavior, the description is largely sufficient. The only minor gap is the lack of explicit guidance contrasting this with create_subscription_checkout or manage_auto_recharge, but the description's clarity compensates.

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%, and both params have clear enum descriptions. The description adds no pack-specific or currency-specific detail beyond the schema, but it does provide helpful context that the credits are 'extra' and 'one-time.' Baseline 3 is appropriate because the schema handles the parameters well.

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 ('Create') and resource ('Stripe-hosted checkout link') and narrows the scope with 'one-time extra credits'. This clearly distinguishes it from subtools like create_subscription_checkout, which handles recurring billing rather than one-time credit purchases.

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 conveys a clear usage context: use this when the user wants to purchase extra credits as a one-time Stripe-hosted checkout. It does not explicitly name alternatives or say when not to use it, but the one-time vs. subscription distinction is sufficiently clear given the sibling tool set.

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