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

Annotations mark this destructive and idempotent, but the description goes well beyond them: no cash refunds, conversion to 12-month studio credit, the 24 h cutoff, and the distinct outcomes for unpaid pre-bookings and voucher-paid bookings. This is exactly the consequence detail an agent needs before a destructive call.

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?

Dense but front-loaded: identity of the booking first, then the mandatory confirmation step and the policy branches. Every sentence conveys a distinct rule (refunds, timing, reschedule, voucher/unpaid edge cases), though the policy block is long enough that a summary line would help scanning.

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?

With no output schema, the description compensates by describing what each outcome produces (credit code, released slot, voucher return). Combined with the 100%-covered two-parameter schema, an agent has everything needed to call it correctly.

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 already 100% for both parameters, so the baseline is 3. The description repeats the reference format example and clarifies that the email must be the one used at booking, but adds little beyond what the schema properties state.

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 and resource ("Cancels a studio booking") plus the exact identification keys (reference and booking email). It is distinguishable from siblings like reschedule_studio_booking, which it effectively names as the alternative path.

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?

Gives explicit preconditions (tell the user the policy, get confirmation), the hard constraint that cancellation under 24 h is not possible, and an alternative action (offer to reschedule, up to 2 times). An agent knows both when to call it and when to route elsewhere.

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