List saved payment requests

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

Annotations already declare readOnlyHint and idempotentHint, but the description adds real value beyond them: the file is never written to, and the embedded cashlink shelf holding link private keys is never opened. That security/scope disclosure is exactly the kind of context annotations cannot carry. It stops short of describing ordering, filtering, or result 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?

Three compact sentences, each carrying distinct information (storage model, prerequisite, safety guarantees), with no filler. The lead is a bare noun phrase rather than the action, but nothing is redundant.

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 single-optional-parameter read tool with no output schema and read-only annotations, the description covers storage location, activation prerequisite, and mutation/secret exposure boundaries. Only the return shape and any result limits are left unstated, which is a minor gap at this complexity.

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?

With one optional parameter and 100% schema description coverage, the schema already explains that 'address' selects the account and defaults to the server's configured address. The description adds nothing about this parameter, so the 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 makes clear that the resource is payment requests stored in a device-local NimBooks backup file, which is specific enough to distinguish it from siblings like create_payment_request or get_statement. It never states an explicit verb and never resolves the name/title mismatch ('list_invoices' vs 'payment requests'), but the noun phrase plus the file-location detail leaves little ambiguity about what is returned.

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 gives a hard precondition — the server must have been started with --backup <path> — which effectively defines when this tool is usable at all. It does not name alternatives or state when not to use it (e.g., for live/server-side requests), so routing to siblings still requires inference.

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