Probes actual root UID, ROM/SDK, and installed command/dependency capabilities, and can initialize the UIAutomator2 helper to reset a failed connection.
Probe actual Root UID, ROM/SDK, installed command/dependency capabilities. initialize_u2 starts the UIAutomator2 helper and resets a failed connection.
| Name | Required | Description | Default |
|---|---|---|---|
| initialize_u2 | No |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v2.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are supplied, so the description carries the full burden. It discloses the probe's targets and the side effect of initialize_u2 (starting a helper process and resetting a broken connection), but says nothing about whether the probe is read-only, whether it restarts ADB or disrupts active sessions, or how long a probe takes.
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?
Two short sentences with no filler, and the primary probe purpose leads. Sentence one is a terse noun list that reads more like a capability dump than prose, which slightly blunts front-loading, but nothing is wasted.
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?
With an output schema present, return values need not be described, and the single parameter is explained. Still, 'dependency capabilities' is unspecified, and the description omits whether the U2 initialization can disturb existing sessions — meaningful context for a diagnostic tool that also mutates connection state.
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 coverage is 0% beyond the bare boolean named initialize_u2, so the description must supply the meaning and it does: the flag starts the UIAutomator2 helper and resets a failed connection. Without that sentence the parameter would be opaque.
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 names specific resources being probed (Root UID, ROM/SDK, installed command/dependency capabilities) and explains the flag's action (starts UIAutomator2 helper, resets a failed connection). It conflates two functions — capability probing and U2 initialization — and never distinguishes itself from the sibling device_diagnostics, so it stops short of 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?
There is one implicit usage trigger: set initialize_u2 when a UIAutomator2 connection has failed. Beyond that, there is no statement of when to call device_doctor versus device_diagnostics, device_connection, or get_device_status, and no preconditions such as whether root is required for the probe.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.