Cancel running slice

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

The description adds behavioral context beyond the annotations by explaining that it can 'unwedge a stale slicing state' and that it is 'Safe when idle'. It also includes a build requirement. The annotations (readOnlyHint=false, destructiveHint=false) are not contradicted, and the description clarifies the operation's nature. It doesn't describe side effects like job status changes, but for a cancel operation, this is adequate.

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 extremely concise and front-loaded with the primary action 'Abort a running slice'. Every sentence adds value: the unwedging use case, the safety note, and the build requirement. There is 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?

For a zero-parameter tool with no output schema, the description is complete. It covers the purpose, a specific use case, safety, and a version constraint. Sibling tools provide surrounding context, and the description sufficiently distinguishes this from them.

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 tool has zero parameters, and the input schema is empty, so there is nothing to explain. According to the rubric, 0 params warrants a baseline of 4. The description adds no parameter-specific info, but none is needed.

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 action: 'Abort a running slice, or unwedge a stale slicing state'. This uses a specific verb (abort/unwedge) with a clear resource (slice), distinguishing it from sibling tools like slice (which starts) and get_slice_status (which reads).

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 guidance on when to use the tool: to abort a running slice or unwedge a stale state, such as after an object outside the bed. It also notes 'Safe when idle' and a version requirement ('needs F2 build'), providing clear context. However, it does not explicitly name alternative tools or when not to use it, so it falls short of a 5.

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