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

Adds substantial context beyond the annotations: reminders anchored to cancelled occurrences are stopped, and the two-phase flow (status='confirmation_required', action_id, plan_token, confirm_action) is spelled out. The destructiveHint is reinforced with concrete consequences.

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?

Front-loads the core action, then scope rules, side effects, and confirmation flow in a compact sequence. Some capitalized emphasis ('REQUIRED', 'PROPOSED') is slightly noisy but each sentence carries 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?

Covers the confirmation protocol and side effects well for a destructive tool, but the event_id/series_id selection is left unexplained and no output behavior beyond the confirmation status is described. Adequate but with a tangible gap for a 3-parameter mutation.

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?

With 0% schema description coverage the description must compensate; it documents 'scope' as required with its three values and defers rules to update_events. However, it never explains event_id vs series_id or when each is needed, leaving a real ambiguity in two of three parameters.

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?

Specific verb+resource: 'Cancel a repeating event' scopes it to series/repeating events, which usefully separates it from the singular delete_event sibling. It is clear what the tool does, though it never explicitly contrasts itself with delete_event.

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?

Explains the required scope argument and that its semantics match update_events, and describes the confirmation gate. It gives no explicit when-to-use/when-not guidance relative to the many other delete_* siblings or vs delete_event/update_events.

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