Cancel an execution task

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

With no annotations, the description carries the burden and it goes beyond a generic cancel by disclosing idempotency and the asynchronous, intent-recording behavior ('records intent; the runtime observes the event and stops work'). It does not cover error cases or the exact stopping guarantee, but the main behavioral traits are disclosed.

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 the primary action and constraint in the first sentence and the behavioral mechanism in the second. No filler or redundancy.

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?

The core contract (cancel non-terminal task, idempotently, event-based) is present and enough for a basic call with the two required parameters. But with no output schema, no annotations, and low parameter coverage, the description leaves the meaning of optional fields and the expected result/outcome unclear.

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 only 20%, so the description must compensate, but it defines none of the parameters except indirectly through 'idempotently'. task_id, reason, by, and expected_version are left to be inferred from names and types, which is insufficient for an agent to use optional parameters correctly.

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?

The description uses the specific verb 'Cancel' with the resource 'non-terminal task' and adds the idempotency constraint, so the action is unambiguous. It is clearly distinct from siblings like tasks (listing) or task_decide (decision-making).

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?

The phrase 'non-terminal task' implies the tool is for active tasks and not finished ones, and the description makes the cancellation use case evident. However, it names no alternatives and gives no explicit when-not-to-use guidance or conditions for choosing a sibling tool.

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