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

With no annotations provided, the description carries the full behavioral burden. It discloses side effects (credits refunded), cost (free), a key error condition (running jobs return 409), and the return value (the canceled job). This is substantive and useful, though it omits details like ownership requirements or irreversibility.

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 three short sentences with no wasted words. The main action is front-loaded, followed by the refund behavior, the running-job restriction, and the no-cost note. Every sentence 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 one-parameter cancellation tool with no output schema, the description covers purpose, conditions, side effects, cost, and return value. It is reasonably complete, though it could have mentioned where to obtain the job id or how to verify a job is queued.

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 0% and the description does not explain what 'id' refers to beyond 'a job.' The single parameter id is left entirely to inference from the tool name. For a low-coverage schema, the description should clarify the id's source or format, but it does not.

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 states a clear verb and resource ('Cancel a queued job') and explicitly ties the tool to jobs started through the API or MCP. It distinguishes itself from sibling tools like getApiJob and listApiJobs by focusing on the cancellation action.

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 explicit conditions: queued jobs can be canceled, running jobs cannot (409). It also notes the operation is free. However, it does not mention alternatives like checking status via getApiJob or listApiJobs first, so guidance is strong but not fully comparative.

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