checkout_request

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

Annotations only say it is a non-read-only, non-destructive, open-world call; the description adds the crucial detail that 'nothing is placed', that a browser review page opens showing total/items/address/card, and that it returns 'pending' asynchronously rather than completing. This is exactly the behavioral context the annotations cannot convey.

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?

Three front-loaded sentences with zero filler: the action and its non-committal nature come first, then the UI flow, then the async contract. Every sentence carries distinct 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?

Despite being a mutation-adjacent, open-world tool, the description covers safety ('nothing is placed'), the user-visible flow, the return status, and the required follow-up call. With an output schema present, no further return-value detail is needed.

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 tool takes zero parameters, so the baseline is 4. The description correctly says nothing about inputs because there are none, and it explains the implicit target ('the current cart'), which is the only semantic an agent needs.

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?

States a specific verb+resource ('approve buying the current cart') and immediately disambiguates from the sibling polling tool by naming checkout_status. An agent can distinguish this from cart, cart_add, and checkout_status without opening any schema.

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?

Clear context for use (approving the current cart) and explicit next-step routing to checkout_status for polling, plus the note that the user can approve or decline. It lacks an explicit when-not condition (e.g., empty cart), but the surrounding guidance is strong.

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