Learn-skills.dev a11y-bridge

Control Android devices via Accessibility Service HTTP bridge. 100x faster than screencap + uiautomator dump. Read UI tree in 50ms, click elements by text/id/description. Use when automating Android apps, controlling a phone via ADB, or building an AI-powered phone agent. Replaces the slow screenshot → parse → coordinate-tap cycle with instant semantic access.

install

source · Clone the upstream repo

git clone https://github.com/NeverSight/learn-skills.dev

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/NeverSight/learn-skills.dev "$T" && mkdir -p ~/.claude/skills && cp -r "$T/data/skills-md/4ier/a11y-bridge/a11y-bridge" ~/.claude/skills/neversight-learn-skills-dev-a11y-bridge && rm -rf "$T"

manifest: data/skills-md/4ier/a11y-bridge/a11y-bridge/SKILL.md

source content

A11y Bridge — Android Accessibility HTTP Bridge

Control Android devices through a 16KB Accessibility Service that exposes the live UI tree over HTTP (

localhost:7333

). ~50ms to read any screen, click by text without coordinate math.

Prerequisites

Android device connected via USB with USB debugging enabled
ADB installed and accessible in PATH
Android SDK (build-tools 34, platform android-34) — only needed to build from source

Setup

Install pre-built APK

Download the latest APK from Releases, then:

# Install
adb install openclaw-a11y.apk

# Enable accessibility service
adb shell settings put secure enabled_accessibility_services \
  com.openclaw.a11y/.ClawAccessibilityService
adb shell settings put secure accessibility_enabled 1

# Forward port
adb forward tcp:7333 tcp:7333

# Verify
curl http://localhost:7333/ping

Build from source (optional)

chmod +x build.sh && ./build.sh

Usage

Read screen (~50ms)

# Full UI tree
curl http://localhost:7333/screen

# Compact mode (only interactive/text elements)
curl 'http://localhost:7333/screen?compact'

Returns JSON with all UI elements: text, bounds, clickable, editable, etc.

Click by text

# Click element containing "Settings"
curl -X POST http://localhost:7333/click \
  -H "Content-Type: application/json" \
  -d '{"text": "Settings"}'

# Click by resource ID
curl -X POST http://localhost:7333/click -d '{"id": "com.app:id/send"}'

# Click by content description
curl -X POST http://localhost:7333/click -d '{"desc": "Navigate up"}'

Tap coordinates

curl -X POST http://localhost:7333/tap -d '{"x": 540, "y": 960}'

Health check

curl http://localhost:7333/ping

Workflow

Read:
```
curl http://localhost:7333/screen
```
→ JSON with all UI elements
Find: Locate target element by text/role in the JSON response

Act:

curl -X POST /click -d '{"text":"Send"}'

→ click by text, no coordinates

Repeat

Multi-device support

When multiple devices are connected, specify the target with

-s <serial>

for all ADB commands:

adb -s <serial> forward tcp:7333 tcp:7333

API Reference

Endpoint	Method	Description
`/ping`	GET	Health check
`/screen`	GET	Full UI tree as JSON. Add `?compact` for interactive elements only
`/click`	POST	Click by `text` , `id` , or `desc` (JSON body)
`/tap`	POST	Tap coordinates `x` , `y` (JSON body)

Performance

	uiautomator dump	A11y Bridge
Read UI	3-5 seconds	~50ms
Click	Calculate bounds → `input tap x y`	`{"text": "OK"}`
Full cycle	5-8 seconds	100-200ms

Fallback

If the A11y Bridge service is not running (check with

/ping

), fall back to traditional ADB commands:

adb shell uiautomator dump /sdcard/ui.xml && adb pull /sdcard/ui.xml
adb shell input tap <x> <y>