job_cancel

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It transparently explains the two possible outcomes (removal if queued, interruption if running), which is valuable. It does not cover edge cases like already-completed jobs or error handling, but for a cancel action, this level of detail is reasonable.

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 concise two-clause sentence: 'Cancel an H3 job: removes it if still queued, interrupts it if running.' Every word adds value, with no redundant information or filler.

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 tool is simple with one parameter and no output schema. The description explains the core behavior but omits details about return values, error scenarios, or job states like 'completed'. While not critical for a cancel tool, the absence of these details leaves the agent with incomplete expectations.

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?

The description does not explain the 'prompt_id' parameter beyond its name, and the schema provides no descriptions (0% coverage). The parameter name is somewhat self-explanatory, but the description fails to clarify its format, origin, or how to obtain it. This leaves a gap in agent understanding.

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 clearly states the tool's purpose: 'Cancel an H3 job'. It also specifies behavior based on job state ('removes it if still queued, interrupts it if running'), which distinguishes it from sibling tools like job_status and h3_image_to_video. The verb+resource structure makes the action unambiguous.

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 implies the primary use case: cancel a job. However, it does not explicitly mention when to choose this tool over alternatives (e.g., job_status to check status first) or any exclusions (e.g., cannot cancel completed jobs). The context is clear but lacks explicit guidance.

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