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

The description discloses critical behavioral facts beyond the annotations: creating the link does not charge money (payment happens on the link), the server calculates the amount (unit price cannot be entered), and no membership is required. It also specifies that the response contains a checkoutUrl to show to the user. These details significantly exceed the sparse annotations and help the agent understand the tool's side 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?

The description is a single paragraph but contains multiple sentences, each contributing useful information: purpose, server-side amount calculation, response usage, payment flow, and pre-creation confirmation steps. It is front-loaded with the core purpose and organized logically, though slightly long. Every sentence earns its place.

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 there is no output schema, the description's mention of checkoutUrl is essential and provided. It covers the full flow from creation to user payment, including important prerequisites like user confirmation and name collection. It does not detail optional parameters or error cases, but the schema covers optional fields, so the description is sufficiently complete for an agent to invoke the tool correctly.

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 description coverage is 100%, so all parameters are already documented. The description adds value by clarifying that only product ID and quantity are needed and that the server computes the amount, ruling out unit price as a parameter. It also emphasizes that customerName must be obtained from the user, reinforcing its requirement. This goes beyond the schema's basic field descriptions.

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 it creates a payment link for card payments, using the verb '만들다' (create) and resource '결제 링크' (payment link). It is unambiguous and distinct from sibling tools like get_checkout_status (which checks status) and signup (which handles registration).

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 for when to use the tool (to create a payment link) and gives specific instructions: confirm product, quantity, and expected amount with the user before creating, and ask for the customer name directly. It also warns that creating the link alone does not charge the user. However, it does not explicitly mention alternatives like 'use get_checkout_status to check status', so it lacks explicit exclusions.

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