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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is covered. The description adds value beyond that by making the irreversibility concrete ('Permanently... cannot be undone'), clarifying there is no trash/recovery path — something the hint alone does not convey. It still omits side effects (e.g. impact on existing syncs of the calendar) and permission requirements.

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 short sentences, zero filler, with the core action front-loaded and the warning immediately after. Nothing needs trimming and nothing is buried.

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 three-parameter destructive tool with full schema coverage and annotations that already carry the safety signal, the description covers the essentials (what it deletes, that it is irreversible). It is slightly thin on interaction effects with the many sync-management siblings in the toolset, which an agent managing mirrored events might need.

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% and all three required parameters (accountId, providerCalendarId, eventId) are documented in the schema itself. The description adds no parameter-level meaning beyond what structured data already provides, so the baseline of 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?

States a specific verb (delete) and resource (an event from a calendar), with scope narrowed by 'from a calendar'. An agent can trivially distinguish this from siblings like update_event, get_event, or list_events without opening any schema.

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?

The description gives no when-to-use context, no prerequisites (e.g. that the account must be connected or the calendar listed first), and does not point to update_event as the alternative when the goal is modification rather than removal. Usage is only inferable from the verb.

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