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

The description claims idempotent-like behavior ('Nothing happened if already cancelled') while the annotations set idempotentHint=false, which is a direct contradiction. It otherwise provides useful non-destructive context, but the contradiction forces the lowest score.

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 sentences with no filler: primary behavior first, then sibling differentiation, then edge case. Every sentence earns its place and the structure supports quick comprehension.

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?

Covers eligible states, non-destructive outcome, sibling distinction, and the already-cancelled behavior; no output schema exists so return format is not required. It is nearly complete, but the idempotency contradiction leaves an unresolved behavioral question for the agent.

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%, so the schema already documents 'request' and 'reason'. The description adds only 'by id', which does not materially enhance parameter understanding; baseline 3 is appropriate.

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?

Clearly identifies the action ('Cancel'), the resource ('a pending or approved request by id'), and the outcome ('keeping its record with status cancelled'). It also distinguishes itself from the sibling leave_reject by intent, so an agent can select it without opening schemas.

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?

Explicitly states the eligible states (pending or approved), names the alternative leave_reject and the differentiating criterion (voluntary withdrawal), and describes the already-cancelled edge case. This gives clear when-to-use and when-not-to-use guidance.

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