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

Beyond the annotations (readOnly=false, idempotent=true), the description discloses critical behavioral traits: the checkout_url is for the user to pay, not the agent; prices are fixed server-side (no client-controlled amount); and the idempotency mechanism via client_request_id. This prevents misuse and matches the annotations.

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 purpose, and every sentence contributes essential information: the deposit amount, the return fields, user payment flow, and idempotency guidance. No fluff or repetition.

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 payment complexity and presence of an output schema, the description is complete: it covers the main flow, user involvement, idempotency, and agent constraints. It enables correct invocation without needing additional contextual information.

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%, with descriptions for both parameters (package enum from list_offers, client_request_id for idempotency). The description reinforces the client_request_id purpose but adds no new semantic detail beyond the schema. Baseline 3 is appropriate.

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 'Create a Stripe Checkout for a package's 50% deposit' – a specific verb, resource, and scope. It is distinct from sibling tools like list_offers or create_upload_url, so the agent knows exactly what this tool does.

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 clear context: show the amount to the user, open checkout_url for the user to approve and pay, and agents never complete payment. It also advises passing a stable client_request_id to avoid duplicate checkouts. However, it does not explicitly state when not to use this tool versus alternatives (e.g., full payment flow), but the '50% deposit' implies scope.

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