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

The description openly discloses that the tool never cancels a booking and never accepts a cancellation token, which aligns with the readOnly, idempotent, and non-destructive annotations. It goes beyond annotations by explaining the security rationale and the required user action. This is strong behavioral transparency with no contradiction.

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 tight sentences with no filler. The most critical behavioral constraint (never cancels, never accepts a token) is front-loaded, and the rest of the description provides actionable security guidance without 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 is sufficient for an agent to understand that this tool cannot perform a cancellation and that the user must follow the secure email link. The only minor gap is that it does not explicitly describe the tool's return value, but the title and overall context make the purpose reasonably clear.

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 tool has zero parameters and the schema coverage is 100%, so the input schema fully documents the interface. The description adds meaningful context about why no cancellation token is accepted, but is not expected to add parameter details. Baseline 4 is appropriate for a parameterless tool.

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 that the tool does not cancel a booking and instead provides secure cancellation instructions via the confirmation email link. It explicitly corrects the action-oriented tool name, distinguishing it from what 'cancel_booking' might imply. This is a specific, non-tautological definition that differentiates the tool from siblings like prebook_stay and start_booking.

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 gives clear context: this tool is for obtaining cancellation instructions, not executing a cancellation. It implicitly tells the agent not to expect cancellation capability and to direct the user to the secure link. However, it does not explicitly name alternatives or state when not to use this tool.

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