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Glama

launch_app

Start an Android app by package name on a connected device, optionally specifying an activity or target device.

Instructions

Launch an app by package name, optionally specifying an activity.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
deviceNoDevice serial from list_devices (omit when exactly one device is connected).
packageYes
activityNo

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.1.0

TDQS

B3.1/5.0
Behavior2/5

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

With no annotations, the description carries the full behavioral burden. It does not say what happens if the app is already running, whether an existing instance is brought to foreground or restarted, what occurs if the package is not installed, or whether an error is returned – all relevant for a launch/mutation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

A single tight sentence with the verb and required input front-loaded and the optional parameter appended. No filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

No output schema exists, so the description should cover behavior and returns. For a simple device-control action the core intent is conveyed, but error/edge-case behavior and the interaction with device selection are left unstated, leaving it only minimally complete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 33% (only 'device' is documented), so the description must compensate for the undocumented params. It does add meaning for 'package' (identifies the app) and 'activity' (optional component to target), but gives no format examples or guidance on finding a package name via list_packages.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Launch an app by package name') with the optional activity scope, which is enough to distinguish it from siblings like open_url, force_stop, and list_packages. It does not explicitly name a sibling, so it stops 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.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

There is no when-to-use guidance, no mention of prerequisites (device connection), and no routing against alternatives such as open_url for deep links or force_stop for restarting an app. Usage is only inferable from the tool name.

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