createInvoiceCreditNote

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

With no annotations, the description carries the burden. It discloses that the amount is in the invoice's currency and that the API stores amounts in cents internally. It also states the return value. However, it does not mention side effects, idempotency, or authentication requirements.

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 extremely concise with two sentences. The first sentence states the purpose, the second provides unit clarification and return value. No superfluous information.

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?

The description is brief but covers the core purpose and unit detail. Given no output schema, 'Returns the created credit note' is minimal but sufficient. However, it lacks context about prerequisites, authentication, or the structure of the returned object.

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%, but the description adds value by explaining the credit note amount unit and internal conversion ('stores amounts in cents internally'), which is not in the schema. The other parameters are adequately described in the schema.

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 it creates a credit note against a specific invoice. It specifies the verb 'create' and resource 'credit note', and the scope is against an invoice. However, it does not explicitly differentiate from sibling tools like refundPayment or voidInvoice, which could be alternatives.

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 does not provide guidance on when to use this tool over alternatives (e.g., refundPayment, voidInvoice). It lacks context about prerequisites (e.g., invoice must exist and be in a certain state) or when not to use it.

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