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

With no annotations, the description carries the behavioral disclosure burden. It goes beyond a simple 'list' statement by revealing that reversed payments remain listed and are marked, and explains the reconciliation rationale. This is a meaningful non-obvious behavior, though it omits details like pagination and response structure.

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 first sentence front-loads the core contents of the ledger, and the second sentence earns its place by explaining a subtle retention behavior.

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-parameter list tool with no output schema, the description covers the key return concepts: payments, remaining balance, overpayment flag, and reversed-payment behavior. It is concise and adequate for an agent to call correctly, though pagination or sorting are not addressed.

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 only parameter, invoiceId, is not described beyond the tool's mention of 'one invoice', which weakly implies it identifies the target invoice. Schema coverage is 0%, so the description should compensate, but it adds little detail about the expected format or how to obtain a valid ID. Still, the single obvious parameter and the tool name make the semantic relatively clear.

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 the tool returns the payment ledger for one invoice, including every payment, outstanding balance, and overpayment status. It is easily distinguished from siblings like invoice_payments_record and invoice_payments_reverse because it explicitly describes a read-only listing operation.

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 phrase 'The payment ledger for one invoice' gives clear context: use this when you need a full payment overview for a single invoice. It does not explicitly name alternatives or state when not to use it, but the read/list framing is enough to guide selection against mutation siblings.

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