Refund receipt

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

Goes well beyond the annotations: it discloses that no external call is made ('Does not contact Stripe or Link'), that the budget is restored, that the operation is once-only (reinforcing idempotentHint=true), and the exact refusal condition. Annotations cover the mutation/idempotency profile, and the description adds the missing operational 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?

Four short sentences, zero filler: the action is front-loaded, followed by the human-confirmation requirement and the two key behavioral constraints. Every sentence carries information an agent needs.

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 destructive mutation with no output schema, the description covers the essentials: what it reverses, the budget side effect, the external-call behavior, the once-only semantics, and the refusal precondition. Nothing needed to call it safely is missing.

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% and there are only 2 parameters, so the schema already documents receipt_id and reason. The description adds no format, constraint, or meaning for either parameter beyond what is already encoded, making the baseline 3 appropriate.

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?

States a specific verb ('Reverse') and resource ('settled dry-run receipt') plus the resulting side effect ('restore that amount to the remaining budget'). This is clearly distinguishable from the sibling budget/proposal tools without opening any schema.

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?

Explicitly flags that this is 'the step a human should confirm,' which tells the agent when to pause for approval, and states the precondition ('Refuses receipts that are not settled_dry_run'). It does not name an alternative tool, but none of the siblings overlaps, so this is a clear context rather than a full routing rule.

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