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

The annotations already flag destructive behavior, but the description adds value by explaining that cancellation is cooperative and that terminal jobs reject it. This tells an agent the operation is not forcibly terminating and may depend on job state.

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?

The description is a single sentence with no filler. The core action and the key caveat about terminal jobs are both front-loaded, making it easy for an agent to parse quickly.

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 two-parameter cancellation tool with destructive annotations and an output schema, the description captures the essential semantics: cooperative cancellation and the terminal-job rejection behavior. It could elaborate on what 'open' means or what happens after cancellation, but nothing critical 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?

Schema coverage is 100% for both parameters, so the schema already documents jobId and reason. The description adds no parameter-specific detail, which is acceptable at the baseline given comprehensive schema descriptions.

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 a specific verb ('cancel') and resource ('job'), and adds meaningful nuance: it requests cooperative cancellation and open jobs are the target while terminal jobs reject it. It does not explicitly call out a sibling tool, so it stops short of full differentiation.

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 description gives clear context: use it for open jobs, not terminal jobs, which reject cancellation. However, it does not explicitly describe alternatives such as job_wait, job_get, or job_report, or state when those would be preferred.

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