build_payment_url

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

With no annotations, the description carries the burden of behavioral disclosure, and it does explain that the tool combines the platform domain with paymentId and operator information. This indicates a pure URL-construction operation rather than a state-changing API call, though it does not explicitly say whether any network call is made or describe the exact return shape.

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 two sentences with no filler. The core action and purpose are front-loaded, and the second sentence adds only the necessary composition detail.

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 low-complexity URL builder with fully documented parameters and no output schema, the description plus schema is sufficient for an agent to invoke it correctly. It could have explicitly placed the tool in the request_payment flow, but the schema's paymentId description already establishes that relationship.

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 input schema already describes all three parameters fully, including the fallback environment variables for operatorId and operatorName. The description only references 'operator information' generically and adds no meaningful detail beyond what the schema provides, 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 names a specific verb ('Build') and resource ('the complete payment URL'), then states the intended purpose: redirecting users to the PLATFORM payment page. This clearly differentiates it from siblings like request_payment, which creates the payment, and the webhook/auth/configuration tools.

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?

It provides clear context: this tool is used after a payment exists, to produce the URL that users should be redirected to. It does not explicitly name alternatives or state when not to use it, but the purpose is unambiguous and the schema ties paymentId to request_payment.

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