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

Annotations already declare destructiveHint=true, openWorldHint=true and idempotentHint=false, so the safety profile is covered. The description adds two things annotations cannot express: an authorization requirement (admins only) and an approval gate by the event owner. The only weakness is that 'Waits' is ambiguous — whether the call blocks or returns a pending status is left unclear.

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?

Three short sentences, front-loaded with the action, then the permission constraint, then the workflow caveat. No filler at all.

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 destructive, non-idempotent mutation with no output schema, the description covers auth and the approval gate but leaves key operational questions open: does the call block until approval, what does it return, and is the deletion reversible or recoverable after approval. Adequate but with clear gaps for a destructive tool.

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 100%: 'group' explains the group URL form and 'event_id' points back to list_events, which is stronger routing than the description provides. The description adds nothing about parameters, so baseline 3 applies.

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 ('Delete a calendar event') that clearly separates it from update_event, create_event, and get_event in the sibling list. It does not explicitly name those siblings, but the resource naming is unambiguous.

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?

'Admins only' establishes a prerequisite for use, which is real guidance. However, there is no statement of when to prefer update_event (e.g., cancel vs. delete) or what happens if the caller is not an admin — behavior is only implied.

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