live_cancel_run

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

With no annotations provided, the description carries full responsibility for side effects. It transparently discloses that the operation force-detaches the run's target tab and stops an in-flight step immediately, and clarifies independence from the currently active tab.

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 slightly detailed but every sentence adds meaningful behavioral context, such as detachment and immediate stop semantics. It remains focused and avoids irrelevant information.

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 description explains the operation's effect and side effects well, which is sufficient given there is no output schema. It does not specify return value or error behavior, but that is not essential for correctly invoking the tool.

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 descriptions cover 67% of parameters, leaving runId undocumented in the schema. The prose clarifies that runId identifies the still-running run to cancel, while project and session are adequately described in the schema.

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 action: cancels a still-running run by runId. It distinguishes this from related cancel operations for scenarios and suites by focusing on the run entity.

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 indicates the condition for use — a run that is still running — and references the familiar Cancel button behavior. It does not explicitly exclude scenario/suite runs, but the runId parameter and naming make the target clear.

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