app-switcher

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

With no annotations provided, the description carries the full behavioral disclosure burden. It does well by flagging that the visible system UI changes, focus may move away from the current app, and the operation times out after 90 seconds. These are meaningful side-effects and constraints beyond a bare action statement.

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?

Three short sentences, each earning its place: the primary action and purpose, the disruptive UI side-effect, and the timeout constraint. The most important information is front-loaded.

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 100% schema coverage, an output schema, and no nested objects, the description is sufficiently complete. It adds the non-obvious behavioral context and timeout. It could mention platform-specific switcher behavior, but that is not essential for most uses.

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 description coverage is 100%, so parameter semantics are already fully documented in the input schema. The description adds no extra parameter context, which is acceptable given the baseline for high schema coverage is 3.

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 a specific action ('Open the device app switcher') and its purpose ('to inspect or change foreground apps'), distinguishing this tool from a generic app launcher or app-state query. It does not explicitly name sibling tools, but the unique system-UI resource is implied strongly enough.

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 when to use the tool: when the agent needs to inspect or change foreground apps via the system app switcher. However, it does not explicitly contrast this with alternatives like `open`, `apps`, or `appstate`, nor does it say when to avoid this tool.

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