Manual refund / pay credit note

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

Annotations already declare destructiveHint=true, so the description adds value by specifying 'records money movement,' which clarifies the financial impact beyond the boolean flag. It also states the gateway prerequisite, providing additional behavioral context.

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, front-loaded with the core purpose, and includes the essential warning at the end. Every word earns its place with no redundancy.

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 covers purpose, prerequisite, and destructiveness. With no output schema, it could mention return values, but for a mutation tool this is acceptable. Minor gap: it does not explicitly contrast with sibling tools like credit_invoice or refund_payment, but that is not critical for completeness.

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 description coverage is 100%; all three parameters have descriptions. The description adds no new parameter-level details beyond the schema, so it meets the baseline but does not exceed it.

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 uses a specific verb ('Record') and resource ('manual refund against an invoice or pay out a credit note'), clearly distinguishing it from automatic refunds (refund_payment) and other credit-related tools. It also clarifies the manual/offline nature upfront.

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 provides clear context: this is for manual (offline) refunds or paying out a credit note, and it requires the gateway. It does not explicitly name alternatives or when-not-to-use conditions, but the 'manual/offline' phrasing implies the distinction from gateway-integrated refunds.

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