# AndroidHomeButton

AndroidHomeButton action, Trigger the system "home" operation on Android devices

Agent View of the PolicyLayer registry record for `AndroidHomeButton`. HTML page: https://policylayer.com/tools/android/androidhomebutton

## Facts

- Tool: `AndroidHomeButton`
- Server: Android (`@midscene/android-mcp`) — https://policylayer.com/tools/android.md
- Install: `npx -y @midscene/android-mcp`
- Homepage: https://www.npmjs.com/package/@midscene/android-mcp
- Risk category: Execute (High risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 6
- Recommended policy verdict: Rate-limited

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `android.deviceId` | string | no | Android device ID (from adb devices) |
| `android.useScrcpy` | boolean | no | Enable scrcpy accelerated screenshots |
| `android.aiActContext` | string | no | Background knowledge passed to aiAct. Default: no extra context. |
| `android.waitAfterAction` | number | no | Wait time in milliseconds after each action execution. Default: 300ms. |
| `android.replanningCycleLimit` | integer | no | Maximum number of replanning cycles for aiAct. Default: model adapter default. |
| `android.screenshotShrinkFactor` | number | no | Screenshot shrink factor before sending images to AI. Default: 1; high values may reduce recognition quality, especially on mobile. |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "AndroidHomeButton",
    "arguments": {}
  }
}
```

## Why AndroidHomeButton is rated High

This tool executes a control operation (returning to home screen) on an Android device. While not destructive or financially harmful, it runs a system-level action triggered by an AI agent without data persistence or modification. The "home" operation is reversible by user interaction but represents execution of external device control whose consequences depend on context (e.g., interrupting critical apps).

From the tool's own definition: "Triggers system 'home' operation on Android devices—an action with device-level effects that cannot be reversed programmatically"

## Use case

AI agents invoke AndroidHomeButton to trigger actions in Android. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call: builds kicked off, notifications sent, workflows started.

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Android:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "AndroidHomeButton": {
      "limits": [
        {
          "counter": "androidhomebutton_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on Android (22)

- `ClearInput` — Destructive — https://policylayer.com/tools/android/clearinput.md
- `act` — Execute — https://policylayer.com/tools/android/act.md
- `android_connect` — Execute — https://policylayer.com/tools/android/android-connect.md
- `AndroidBackButton` — Execute — https://policylayer.com/tools/android/androidbackbutton.md
- `AndroidRecentAppsButton` — Execute — https://policylayer.com/tools/android/androidrecentappsbutton.md
- `CursorMove` — Execute — https://policylayer.com/tools/android/cursormove.md
- `DoubleClick` — Execute — https://policylayer.com/tools/android/doubleclick.md
- `DragAndDrop` — Execute — https://policylayer.com/tools/android/draganddrop.md
- `KeyboardPress` — Execute — https://policylayer.com/tools/android/keyboardpress.md
- `Launch` — Execute — https://policylayer.com/tools/android/launch.md
- `LongPress` — Execute — https://policylayer.com/tools/android/longpress.md
- `Pinch` — Execute — https://policylayer.com/tools/android/pinch.md
- `PullGesture` — Execute — https://policylayer.com/tools/android/pullgesture.md
- `RunAdbShell` — Execute — https://policylayer.com/tools/android/runadbshell.md
- `Scroll` — Execute — https://policylayer.com/tools/android/scroll.md
- `Swipe` — Execute — https://policylayer.com/tools/android/swipe.md
- `Tap` — Execute — https://policylayer.com/tools/android/tap.md
- `Terminate` — Execute — https://policylayer.com/tools/android/terminate.md
- `take_screenshot` — Read — https://policylayer.com/tools/android/take-screenshot.md
- `android_disconnect` — Write — https://policylayer.com/tools/android/android-disconnect.md
- `assert` — Write — https://policylayer.com/tools/android/assert.md
- `Input` — Write — https://policylayer.com/tools/android/input.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=android · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/android