android_launch_app

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only states the action (launch) but does not explain side effects such as bringing the app to the foreground, what happens if the package is not installed, whether it waits for launch completion, or how non-optional parameters like activity and deviceId affect behavior. The description is minimal and relies on the name for implicit meaning.

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 sentence that opens with the core verb and resource. It is direct, front-loaded, and contains no filler. It efficiently conveys the essential information without unnecessary elaboration.

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 tool with three parameters, no output schema, and no annotations, the description is under-specified. It does not clarify whether optional parameters are truly optional or how they affect behavior, nor does it mention any prerequisite (e.g., device must be connected) or post-launch state. The tool is relatively simple, but the description could be more complete about observable results and edge cases.

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% – all parameters (packageName, activity, deviceId) have descriptions in the schema. The description adds examples of package names, which reinforces the format but does not add new meaning beyond what the schema already states. Since the schema already documents parameters, the description provides marginal added value, so a baseline of 3 is appropriate.

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 purpose: 'Launch an Android application by its package name.' It specifies the verb (launch), the resource (Android application), and the identifying parameter (package name). It is distinct from siblings like android_tap or android_swipe, which handle interaction rather than launching.

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 provides no guidance on when to use this tool versus alternatives. It does not mention that launching an app is a prerequisite for other actions, nor does it advise against using it for already-running apps. Given the sibling list includes many interaction tools, some contextual advice would help, but none is present.

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