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

The description goes far beyond the annotations by revealing critical behavioral traits: it verifies the guest first, returns a first-party URL and policy, never cancels in conversation, provides no refund/penalty estimates, and the reservation remains active until the page reports success. This is exactly the kind of context an agent needs to avoid misleading the user. No contradiction with annotations (readOnlyHint=false, idempotentHint=true, destructiveHint=false).

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 dense with valuable information and no filler, but it is a bit long and repeats the core 'not cancelled until confirmed' point twice. Every sentence earns its place, though slight tightening could improve scannability.

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 output schema exists and annotations are present, the description covers all essential operational details: what is returned, the confirmation flow, email notification, and the non-destructive nature of the tool. An agent has everything needed to invoke it correctly and set user expectations.

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?

The input schema already describes all three parameters with 100% coverage, so the baseline is 3. The description adds only an indirect hint that these parameters are used for guest verification ('After verifying the guest'), but no additional syntax, format, or semantic detail beyond 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?

Clear verb+resource: creates a secure cancellation handoff for a hotel reservation. It explicitly states what the tool does, what it returns (policy + URL), and what it does NOT do (never cancels in conversation), which sharply distinguishes it from siblings like lookup_booking or book_hotel.

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 makes the use case obvious: when a guest wants to cancel, this tool initiates a handoff rather than directly cancelling. It clearly sets expectations that the guest must complete cancellation on the secure page. It does not explicitly name alternatives or exclusion conditions, but the context is strong enough for an agent to select it appropriately.

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