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

Annotations already declare destructiveHint=true and idempotentHint=true, covering the safety profile. The description adds a meaningful constraint—only queued or running runs can be cancelled—but does not disclose what happens after cancellation (e.g., irreversible, async, effect on results). This adds some value but not rich behavioral context.

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, front-loaded sentence with zero wasted words. It conveys the action, resource, and constraint efficiently.

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, destructive, idempotent tool, the schema and annotations cover most of what an agent needs. The main gap is that no output schema exists and the description does not mention what the tool returns after a successful cancel or how errors (e.g., run already finished) are surfaced, which would be useful but not critical.

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 input schema covers the sole parameter run_id with 100% description accuracy ('AgentFarm run identifier'). The tool description adds no additional parameter meaning beyond what the schema already provides, so the baseline of 3 applies.

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 specific verb ('Cancels'), a resource ('AgentFarm run'), and a scope qualifier ('authenticated queued or running'). This clearly distinguishes it from sibling tools like create_run, get_run_status, and get_run_result, so an agent knows exactly what the tool does.

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 this tool is only for queued or running runs, but it does not explicitly say when to use it versus alternatives or mention any exclusions. Context about siblings is present in the signal data but not referenced in the description itself.

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