open_app

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

No annotations are supplied, so the description carries the full behavioral burden, yet it says nothing beyond input format. It does not state what happens if the app is not installed, whether the call waits for the app to foreground, or what it returns; for a launch action with zero annotation coverage that is a real gap.

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?

A single sentence that front-loads the action and packs the format guidance into one parenthetical. Nothing is wasted and nothing needs to be moved.

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 one-parameter tool this is close to sufficient on inputs, but with no annotations and no output schema the description should still say what a call returns or how failure looks (app missing, device not ready). The input side is complete; the outcome side is absent.

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 0% and the single `name` parameter is a bare string, so the description does the work by explaining that it accepts either a display name or a package identifier. The parenthetical examples ("whatsapp", "camera", "com.whatsapp") give the agent an unambiguous format to imitate; only edge cases like partial matches are unaddressed.

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 and resource ("Open an app") and immediately disambiguates the input form with concrete examples of both a friendly name and a package name. It does not name sibling tools such as list_apps or open_url, so the reader must infer the boundary, which keeps it short of a 5.

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 only implied: an agent can infer it should call this when it wants an app launched rather than a URL or a raw shell command. There is no explicit when-to-use versus open_url or list_apps, and no prerequisite such as a selected/connected device.

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