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

The description adds useful behavioral context beyond the destructiveHint annotation by stating that a durable refund receipt is created and that the refund method follows merchant settings unless overridden. It does not describe all consequences of cancellation, but the annotation covers the destructive nature.

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 main action and then a concise detail about refund behavior. Every word contributes value 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 the core action and the refund behavior, and an output schema exists to explain return values. It does not elaborate on idempotency or retry semantics, but the idempotencyKey parameter description in the schema covers that. Overall adequate for a destructive mutation 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 description coverage is 100%, providing baseline 3. The description adds extra semantics for refundMethod by explaining the default merchant setting, which exceeds the baseline. 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 the tool cancels a booking and creates a durable refund receipt, using a specific verb and resource. It distinguishes itself from related booking tools like confirm_booking or complete_booking by focusing on cancellation and refund receipt creation.

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 implies the tool is used to cancel a booking, but it does not provide explicit guidance on when to use this tool versus alternatives, nor any exclusions or prerequisites. It mentions refundMethod override, but no context on when to choose manual vs account_credit.

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