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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is known. The description adds the creator-only authorization requirement and the valid task states, but says nothing about downstream effects such as what happens to assignees, escrow, or points, or 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?

A single short sentence with the authorization constraint front-loaded and zero filler. Every word carries 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 mutation tool with no output schema, the definition covers who may call it and on which states, but omits the consequences of cancellation and any confirmation or irreversibility note. An agent can call it correctly but cannot predict the outcome.

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 task_id, reason and idempotency_key are already documented in structured form. The description adds no additional meaning about when a reason is expected or how the idempotency key interacts with retries, so this sits at the baseline.

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 task) and narrows the scope to open or assigned tasks, which separates it from siblings like apply_task or assign_task. It does not explicitly name a contrasting sibling, so it stops short of a 5.

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?

'Creator only' gives a clear authorization precondition and 'open or assigned' gives the state precondition for legitimate use, which is real when-to-use guidance. It does not mention alternatives (e.g. opening a dispute instead of cancelling) or what to do for tasks in other states.

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