Launch app

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

No annotations are provided, so the description carries the full behavioral burden, and it discloses almost nothing beyond input formats. It does not state that the action executes on a connected device, what happens if the app is not installed or the alias is unknown, or whether launching is idempotent/side-effecting. The re-observation and screenshot behavior is only visible through parameter names, not explained in the description.

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?

One sentence, front-loaded with the action and the three accepted forms, with the alias enumeration appended as directly usable data. No filler or repetition.

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 4-parameter tool with no annotations and no output schema, the description covers input formats well but is silent on the operational context (device connectivity, error cases) and does not hint at what the response contains. Adequate to call correctly, but thin on surrounding context.

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 the baseline is 3. The description goes beyond the schema's terse 'Package, component, or alias' by enumerating real aliases (settings, chrome, camera, gmail...) and showing concrete package and component syntax, which meaningfully reduces input-format guessing.

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?

States a specific verb (Launch) and resource (an app) and enumerates the three accepted identifier forms with concrete examples (com.android.settings, pkg/.Activity, and the alias list). An agent immediately knows what the tool does. It does not explicitly contrast with siblings like phone_apps or phone_observe, but the launch-vs-list/dump distinction is self-evident.

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?

Usage is implied by the imperative 'Launch an app' and the alias list gives practical guidance on valid inputs. However, it never states preconditions (e.g. a device must be connected via phone_connect first) or when to prefer this over phone_apps/phone_observe. No explicit when-to-use or when-not-to-use guidance is present.

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