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

Annotations already establish it is a safe, closed-world read. The description adds useful output context beyond the annotations: the possible states, that 'paid' carries who/network/transaction and on-chain confirmation, and that attempts are included. It stops short of describing error or missing-record behavior.

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?

One dense sentence, front-loaded with the resource identity and then the returnable states; no filler or restated title.

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 no output schema, the description carries the return-value burden and does so by naming the states and paid-details, which is enough for a single-record read-only lookup. Minor gaps remain around not-found/error handling and the api_token fallback, though the latter is covered in the schema.

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 both parameters (api_token auth pattern, request_id) are fully documented in the schema, so the description adds nothing parameter-level. Baseline 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 resource (a payment request's authoritative record) and enumerates its meaningful states (open, paid, cancelled), so an agent can tell this is a status lookup rather than list_payment_requests or pay. It never states the verb 'retrieve/look up' explicitly, but the intent is clear from 'record' plus the request_id requirement.

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?

No when-to-use guidance is given, nor any mention of the obvious siblings: when to call this versus list_payment_requests (all requests) or pay/request_payment (acting on a payment). Usage must be inferred entirely from the name and description.

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