Stop async focus trace

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

Annotations provide no destructive or readOnly hints, but the description adds transparency by noting that large traces write samples to an artifact, a significant side effect. It also describes the output fields. However, it does not clarify whether stopping is idempotent or if it destroys the session beyond retrieval.

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 two sentences, front-loaded with the core purpose and output. Every sentence adds value without 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?

Given the simplicity of the tool (stop a session and return data), the description is mostly complete. It mentions return fields and the artifact side effect. However, it omits linking `focusSessionId` to the start tool and does not leverage the presence of an output schema.

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 coverage is only 33%, and the description does not explain the `includeAllSamples` parameter. It mentions 'samples' but lacks specifics. The `focusSessionId` is not described in context, relying on format alone. The description needs to compensate for the low schema coverage but falls short.

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 ('Stop an async focus session') and what it returns ('focus change events plus samples'). It distinguishes from sibling tools like mobile_focus_trace_start by focusing on stopping. The preference for `changes` adds specificity.

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 hints at usage with 'Prefer `changes` for flash/launcher hunting', but does not explicitly state when to use this tool versus alternatives like mobile_focus_trace_start. No exclusion criteria or prerequisites are mentioned.

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