agent-droid

An agent-browser for Android. Drive a real device or emulator over adb with a tight snapshot → ref → act loop: snapshot the on-screen accessibility tree into ref-tagged interactive elements, then tap/type/swipe by ref — or by visible text. Built to be driven by AI agents (machine-readable --json, single self-contained commands) and pleasant for humans too.

agent-droid snapshot
# @e5 [input]  "you@example.com" (720,2180)
# @e6 [input]  "********" [password] (720,2426)
# @e7 [button] "Sign In" (720,2612)

agent-droid type @e5 "you@example.com"
agent-droid type @e6 "hunter2"
agent-droid tap  "Sign In"          # target by visible text — no ref lookup needed

Why

Raw adb shell input tap X Y is brittle: you eyeball pixels off a scaled screenshot, and the tap misses the moment the soft keyboard or a re-layout moves things. agent-droid instead resolves every action against the live view hierarchy and re-finds the target by node identity (class / content-desc / text) right before acting — so taps survive layout shifts. Two more things make it agent-friendly:

• Animation-proof snapshots. Plain uiautomator dump waits for the UI to go idle and fails with could not get idle state on any screen with a continuous animation (common in React Native / Reanimated / game loops). agent-droid setup installs a tiny on-device UiAutomator instrumentation that dumps with the idle-wait disabled, so snapshots work mid-animation. It emits the identical XML schema, so nothing else changes.
• One call, not four. tap "Sign In" resolves visible text against a fresh snapshot and taps it — no snapshot → read → pick-ref → tap round-trip. --json gives exact, parseable output. --then (opt-in) echoes the next screen.

Requirements

• Node.js ≥ 18
• adb on your PATH (Android Platform Tools), with a device/emulator connected (adb devices shows it as device).
• For the animation-proof dumper: nothing to build — prebuilt APKs are bundled and installed by agent-droid setup. (To rebuild them yourself you need a JDK 17 + Android SDK; see MAINTAINING.md.)

Works on macOS, Linux, and Windows. The driver is app-agnostic — it dumps whatever app is in the foreground.

Install

npm install -g agent-droid      # provides `agent-droid` and the short alias `droid`
agent-droid setup               # one-time per device: installs the dumper
agent-droid doctor              # sanity check: device, foreground app, dumper status

Or run without installing:

npx agent-droid doctor

The loop

1. agent-droid snapshot — print the interactive elements as @eN refs.
2. Act on one: tap @e7, type @e5 "…", key ENTER, swipe up.
3. agent-droid snapshot again after every screen change — refs are per-snapshot.
4. Verify with wait "text" (blocks until it appears) or logs.

Commands

Command	Purpose
doctor	Devices + foreground app + dumper status. Never throws.
setup	One-time per device: install the animation-proof dumper.
snapshot [query]	Dump the tree as @eN refs; query filters by name substring.
tap <@eN | "text" | X Y>	Tap a ref, a visible-text match, or raw coordinates.
type <@eN | "text"> "value"	Focus the target, clear it, then type.
key <NAME|code>	Keyevent: BACK ENTER TAB HOME DEL SEARCH ESCAPE or a raw keycode.
swipe <up|down|left|right>	Scroll/swipe gesture.
wait "text" [ms]	Poll until text appears (default 8000ms).
current	Foreground package/activity.
logs [filter] [tail]	Tail app logcat. --tag <T> (default ReactNativeJS; '*' = all).
screenshot [file]	Save a PNG (default droid-shot.png).
--help	Full reference.

Targeting: refs vs. text

@eN refs are the primary, exact handles — they carry node identity and survive layout shifts. Visible-"text" targeting is a convenience addon: it resolves against a fresh snapshot in one call (picking the most specific match when several share the text). Reach for a ref when the text is ambiguous or duplicated.

Flags

• --serial <id> — target a specific device (default: first online).
• --tag <T> — logcat tag for logs (default ReactNativeJS; '*' for all).
• --json — machine-readable output (no human text); ideal for agents.
• --then — off by default. After an action, re-snapshot and print the new screen. Opt in only when you want the result echoed — it adds a full snapshot to the output.

Example: machine-readable, one call per step

agent-droid tap "Sign In" --json
# {"action":"tap","ref":"e7","name":"Sign In","cx":720,"cy":2612,"stale":false}

agent-droid snapshot --json | node -e 'JSON.parse(require("fs").readFileSync(0)).forEach(r=>console.log(r.ref,r.name))'

Limitations

• iOS is not supported — adb is Android-only.
• Soft-keyboard occlusion: when the IME covers a field, the dump may return only the keyboard window; type then falls back to cached coordinates. Dismiss the keyboard or scroll the field into view if a type doesn't land.
• logs defaults to the ReactNativeJS tag (handy for RN apps). For other apps pass --tag <YourTag> or --tag '*'.

How the animation-proof dumper works (short version)

agent-droid setup installs two tiny APKs: an empty host app and a UiAutomator instrumentation test. The test sets Configurator.setWaitForIdleTimeout(0) and calls dumpWindowHierarchy(...), returning the XML through an am instrument status Bundle (the one transport that works on every device — file writes are blocked by scoped storage, and test stdout isn't forwarded). UiAutomation reads the whole screen system-wide, so it dumps any foreground app. Full rationale, build steps, and the debugging guide are in MAINTAINING.md.

License

MIT