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

Annotations already declare destructiveHint, idempotentHint, and openWorldHint. The description goes beyond them by spelling out what is actually affected (stored event removed vs. backing post cancelled) and by detailing the idempotency_key retry contract, which is genuinely useful context for a destructive operation.

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 short sentences, front-loaded with the core action, then the behavioral nuance and retry contract. No filler; the only minor redundancy is 'Returns the deletion result,' which is near-tautological.

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 mutation with no output schema, the annotations cover the safety profile and the description covers the dual deletion semantics and idempotency behavior. The main gap is the undocumented `query` and `brand_id` parameters, but the essentials for correct invocation are present.

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 only 40% across 5 parameters. The description adds meaning for `id` (the event identifier) and `idempotency_key` (retry-safety semantics), but says nothing about brand_id, workspace_id scoping behavior beyond 'selected workspace', or the nested `query` override object.

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 and resource ('Delete a calendar event by id') and adds scope ('from the selected workspace'). It also clarifies a non-obvious behavior—deletion may manifest as post cancellation—which helps distinguish it from the many delete_* and cancel_* siblings, though it never names a sibling explicitly.

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?

Usage is implied by the mention that it 'cancels the post when the calendar uses scheduled posts as its backing store,' which hints at overlap with cancel_post/cancel_scheduled_post. However, it never states when to prefer this tool over those alternatives, nor any prerequisites or exclusions.

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