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

Annotations already declare destructiveHint=true, readOnlyHint=false, idempotentHint=false and openWorldHint=true, so the safety profile is carried by structured data. The description still adds real value beyond that: the required `content:write` scope, the fact that the first call is a no-op validation pass, and that unknown fields are rejected by name. What it omits is what the second call returns and whether cancellation is reversible.

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 action, then the permission requirement, then the two-call protocol in three tight sentences. No filler, and the ordering matches the order an agent needs the 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?

For a destructive, non-idempotent mutation with no output schema, it covers auth, the dry-run/confirm mechanic, and the rejection behavior of bad arguments. The remaining gap is the shape of the second call's response and any reversibility note, which are minor against what is provided.

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 50%, and the description compensates well for `confirm_token` — explaining it must be omitted on the first call and echoed from the first call's response. The required `id` parameter is left completely unexplained in both the description and the schema, so it does not fully bridge the coverage 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?

Names a specific verb and resource ("Cancel a live event") so the action is unambiguous. However, it never distinguishes cancel from nearby siblings such as delete_live_event, archive_live_event, or unpublish_live_event, which an agent must choose between.

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?

Gives a clear two-call procedure: call once to validate and obtain a summary plus confirm_token, show the summary to the person, then call again with the token once they agree. That is strong when-to-call guidance for the flow itself, but there is no guidance on when cancellation is the right operation versus deleting or archiving the event.

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