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

Annotations already declare destructiveHint=true and idempotentHint=false, but the description goes well beyond them: it discloses that the first call is a no-op preview returning {cancelled:false, requires_confirm:true}, that every host's tentative holds and any confirmed event are released, that a booked invitee receives a cancellation email, and that the action is irreversible. That is exactly the behavioral context a destructive tool needs.

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-loaded correctly with the destructive warning and two-step mechanic, but the two-step explanation, the cancellation-email fact, and the 're-propose to start over' advice are each stated twice (once in the lead paragraph, once under 'When to use'). The duplication inflates the text without adding 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?

An output schema exists, so the description is not obliged to detail return values, and it still names the final-state return. Combined with the side-effect inventory, the irreversibility warning, and the two-step protocol, an agent has everything needed to invoke this correctly.

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 100%, so the per-parameter baseline is 3. The description adds protocol-level meaning the individual schema fields do not convey on their own — the ordering of the unconfirmed preview call before confirm:true, and the requirement to obtain user confirmation in between — which is more than a restatement of the 'confirm' field doc.

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 ('Cancel a meeting') and immediately scopes it against the family of meeting tools by describing the cancellation side effects and the 're-propose to start over' path. An agent can distinguish this from propose_meeting or reschedule_meeting without opening a 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?

'When to use: When plans change' plus the explicit two-step protocol (call without confirm, confirm with the user, call again) gives clear operational context. It does not explicitly name reschedule_meeting as the alternative when the user wants a different time, so it stops short of full alternative routing.

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