Record a payment

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

The description explains behavioral consequences: settling invoices updates their payment status, confirmable with get_invoice_payment_status. It also notes that this does not issue an invoice. Annotations already indicate it's not read-only and not destructive, which aligns. No contradictions.

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 concise (three paragraphs) and front-loaded with the main purpose. Each paragraph adds essential information: usage trigger, invoice handling, type guidance, and distinction from create_invoice. No unnecessary words or repetitions.

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 the tool's complexity (17 parameters, nested objects) and lack of output schema, the description covers key aspects: when to use, how to handle invoices, type selection, and relationship to invoices. It doesn't detail every parameter, but the schema compensates. The description is sufficient for an agent to correctly invoke the tool.

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% with detailed descriptions for each parameter. The description adds value by explaining the purpose of invoices, the meaning of type values, and conditions for seriesName. However, it doesn't cover every parameter beyond what the schema provides, so it provides moderate additional guidance.

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 verb ('Record money received from a client') and the resource (payment). It distinguishes itself from create_invoice by explicitly stating 'This does not issue an invoice; use create_invoice for that.' The title 'Record a payment' aligns with the description.

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 gives explicit usage guidance: 'Use this when the user says a customer has paid.' It explains when to pass invoices vs. leave empty, and advises to ask the user rather than guessing for the type. It also mentions an alternative tool (create_invoice) for issuing invoices.

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