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

Annotations already declare destructiveHint=true, idempotentHint=false and openWorldHint=true, so the safety profile is covered. The description adds genuine context beyond them: a precondition (the interview must not have started) and a side effect ("The other participant is told"), which an agent needs to know before calling. It does not say whether the slot is freed or whether the cancellation is reversible, keeping it below a 5.

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 with no waste; the action and the precondition come first and the side effect follows. Every clause earns its place.

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 single-parameter destructive mutation with full annotation coverage and no output schema, the description supplies the essentials: scope, precondition, and the notification side effect. It could go further on reversibility or on where to get the id, but nothing critical to correct invocation is missing.

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?

Only one parameter, and schema coverage is 100% with "The mock interview's id." already documented. "by id" in the description restates the schema rather than adding format, sourcing, or validation guidance. Baseline 3 applies since the schema does all the work.

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 one of the person's upcoming mock interviews") plus a scoping constraint ("before it starts") and the lookup key ("by id"), which cleanly separates it from booking/hosting siblings like buddy_mock_book. It stops short of naming a specific alternative tool, but the action is unambiguous.

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?

"Upcoming ... before it starts" implies the valid window for use, but there is no explicit exclusion (e.g. what to do for past or in-progress interviews) and no pointer to buddy_mock_list for obtaining the id. Usage context is implied rather than stated.

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