Create Vive checkout

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

Annotations already indicate readOnlyHint=false and idempotentHint=false. The description adds important behavioral context: this is a real paid transaction that returns a payment URL and should only be invoked after user confirmation, which is beyond what the annotations alone 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?

Two compact sentences deliver the core purpose, the critical side-effect warning, and a mandatory user-confirmation instruction. Every word earns its place, and the main behavioral caution is front-loaded.

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?

With one simple parameter, an output schema, and annotations covering safety traits, the description is sufficient. It names the authenticated account context, the payment nature, the return value, and the required user confirmation—nothing essential is missing.

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 the sole parameter, vive_amount, is adequately described as 'Amount of Vive to purchase.' The description adds useful context about the purchase flow but does not add new meaning to the parameter itself, so the baseline of 3 applies.

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-resource pair ('Start a paid checkout to buy Vive points') and states the key output ('return the payment URL'). It is clearly distinct from sibling tools, none of which handle Vive checkout.

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 gives strong situational guidance by warning that this 'begins a real purchase flow' and instructing the agent to 'always confirm the amount with the user before calling.' It does not explicitly name alternatives, but the context makes the appropriate usage clear.

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