cancel_event

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

Goes beyond annotations by stating the event is 'marked cancelled and excluded from future availability calculations' and details recurring series behavior. No contradiction with annotations (destructiveHint, idempotentHint).

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 well-structured sentences that front-load the purpose and efficiently explain optional parameters and recurring behavior. No redundant or unnecessary text.

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?

Covers cancellation effect, optional parameters, and recurring series handling. No output schema exists, so return behavior is not required. Could add note on irreversibility, but destructiveHint already implies it.

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 100% with basic descriptions; the tool description adds meaningful context: calendar_id's optionality and fail-fast benefit, occurrence_start's role for recurring events. This enhances understanding 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?

Description clearly states the tool deletes or cancels an event from a calendar, distinguishing it from siblings like confirm_event, release_event, or create_event. The verb 'cancel' and resource 'event' are specific.

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?

Explicitly says when to use the tool ('to remove, cancel, or delete any scheduled event or appointment'). Provides guidance on optional parameters (calendar_id, occurrence_start) and explains behavior for recurring series. However, no explicit 'when not to use' or comparison to alternatives like release_event.

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