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

No annotations provided, so description carries full burden. It discloses the critical behavior of emailing cancellation to guests and irreversibility. However, it doesn't mention permissions, failure handling, or recurrence specifics beyond 'event or occurrence'.

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?

Two sentences, zero fluff, action first. Every word is necessary, and the critical caution about guests is prominently placed.

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 tool with no output schema and no annotations, the description covers essential behavior but omits guidance on sourcing eventId (e.g., from list_outlook_calendar_events). A brief mention would make it complete.

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 50% (mailbox has a description, eventId has none). The description adds no parameter information. eventId remains completely undocumented, leaving the agent unsure how to obtain it. Description fails to compensate for the schema gap.

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?

The description clearly states the verb 'Delete' and the resource 'event or occurrence', distinguishing it from sibling tools like delete_outlook_calendar which deletes an entire calendar. No ambiguity about what it does.

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?

It gives clear guidance on the destructive nature (immediate, irreversible, emails guests) and instructs to ask user confirmation. It doesn't explicitly name an alternative tool, but the caution is strong and implies when to avoid using it.

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