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

Annotations already declare destructiveHint=true and idempotentHint=false, but the description adds materially new behavior: the action is irreversible, Lunacal emails attendees, and allRemainingBookings also kills the rest of a recurring series. Those are consequences an agent cannot infer from the annotation flags alone.

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, front-loaded with the identifier requirement and the confirmation precondition, followed by consequences and the optional parameter. Nothing is redundant and no sentence could be dropped without losing information.

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 3-parameter destructive tool with no output schema, the description covers irreversibility, attendee notification, recurring-series scope, and the conditional reason field. It stops short of saying what the call returns or how partial failures on a series are reported, which would fully close the loop.

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 coverage is 67% and the undocumented parameter is cancellationReason, which the description explains ('If Lunacal requires a reason, pass cancellationReason'). It also adds the uid-vs-numeric-id distinction that the schema's 'Booking uid' label does not make explicit.

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 ('Cancel a booking') and immediately pins down the identifier ('by uid (not the numeric id)'), which is exactly the ambiguity an agent would otherwise hit. The action is plainly distinguishable from siblings like reschedule_booking and list_bookings.

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 a real precondition ('Confirm with the user first') and a conditional usage rule ('If Lunacal requires a reason, pass cancellationReason'). It does not name an alternative action such as reschedule_booking when the user may not actually want to cancel, so the when-not guidance is incomplete.

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