Manos

A CLI Model Context Protocol server for ad-hoc UI testing of Android & iOS apps — purpose-built for the exploratory, test-free loop where an LLM agent pokes at an app and reacts to what it sees.

It controls Android emulators/devices (adb) and iOS simulators (xcrun simctl, with idb for native UI interaction) and exposes 39 tools over stdio.

manos gives an agent a tight act → observe loop, device-condition control, crash/log capture, network capture for debug builds, OCR targeting for off-tree elements, an accessibility audit, and session recording that promotes an ad-hoc exploration into a replayable regression test in one call. See IMPROVEMENTS.md for the design rationale and roadmap.

Install

npm install -g manos-mcp     # install the CLI, or run on demand with: npx -y manos-mcp
manos doctor             # check toolchain + list devices & capabilities

Requires Node 20+. Most MCP clients can launch manos on demand with npx — no global install needed; see Register with an MCP client. Working on manos itself? See From source.

iOS UI interaction works without idb by falling back to Maestro (slower; call launch_app first). Android UI inspection falls back from uiautomator dump to maestro hierarchy automatically when the on-device UiAutomation connection is contended.

Register with an MCP client

Each tab launches manos with npx -y manos-mcp serve, which fetches and runs the published package on demand — no clone or global install required. (If you installed globally with npm install -g manos-mcp, use a bare manos serve instead.)

claude mcp add manos -- npx -y manos-mcp serve
claude mcp list            # verify

{
  "mcpServers": {
    "manos": { "command": "npx", "args": ["-y", "manos-mcp", "serve"] }
  }
}

{
  "mcpServers": {
    "manos": { "command": "npx", "args": ["-y", "manos-mcp", "serve"] }
  }
}

{
  "servers": {
    "manos": { "type": "stdio", "command": "npx", "args": ["-y", "manos-mcp", "serve"] }
  }
}

{
  "mcpServers": {
    "manos": { "command": "npx", "args": ["-y", "manos-mcp", "serve"] }
  }
}

command: npx
args:    ["-y", "manos-mcp", "serve"]
transport: stdio

From source

For working on manos itself, or to pin a local build instead of the published package:

git clone https://github.com/ryanperkins/Manos-MCP.git && cd Manos-MCP
npm install            # also builds via the prepare script
npm run build          # or rebuild after changes
node dist/cli.js doctor

Register the local build by pointing your client's command/args at node /ABS/PATH/to/Manos-MCP/dist/cli.js serve instead of the npx form above.

CLI

manos serve      Start the MCP server on stdio (default)
manos doctor     Toolchain + connected devices + per-device capabilities
manos devices    List connected devices (tab-separated)
manos --help

The tools

Full reference and the Android vs iOS comparison matrix are in docs/index.html. Highlights:

• Core: list_devices, device_capabilities, inspect_screen, take_screenshot.
• Authored flows: run_flow runs a declarative flow locally; cheat_sheet gives the syntax. export_flow (below) turns a recorded session into one.
• Act + observe: tap, long_press, input_text, press_key, swipe — each takes a selector (id/text/resource_id/accessibility) or coordinates and returns the resulting screen (observe: screen | diff | screenshot | none).
• Smart waits / assertions / search: wait_for, assert, find_elements, and find_text (OCR the screenshot to locate text the accessibility tree misses — styled buttons, canvas/Flutter/game UIs, WebViews). Targeting falls back to OCR automatically when a text selector finds nothing in the tree, or force it with tap{text, ocr:true}.
• App state: launch_app, stop_app, clear_app_state, open_deeplink, set_permission.
• Device conditions: set_appearance, set_orientation, set_locale, set_network, set_location, set_font_scale, set_status_bar, push_notification, and set_conditions (apply many at once / named presets like offline, accessibility, screenshot).
• Diagnostics: get_logs (with crash/ANR detection), a11y_audit.
• Network capture (debug apps): network_start/network_requests/network_clear/network_stop — capture decrypted HTTP filtered to specific endpoints. Android hooks OkHttp via Frida (works through HTTP/2, pinning, proxy-bypass); iOS Simulator uses mitmproxy + a simctl-trusted CA. See NETWORK.md.
• Network mocking (Android): network_mock — manipulate live API responses to test hard-to-reproduce states: override status/headers, replace the body, regex-rewrite a field in the live body (keep the rest), or inject latency. Rule-based (URL regex + method), hot-reloads, no separate mock server or build change. Rides the Frida/OkHttp capture hook (per-process, no host-proxy disruption — network_start first). iOS response mocking is in development. See NETWORK.md.
• Recording: start_recording → act → export_flow (replayable Maestro flow) or export_report (self-contained HTML report: screenshot timeline + flow + logs + captured network).

A typical loop:

list_devices → inspect_screen → tap{text:"Login", observe:"diff"} → input_text{...} → wait_for{text:"Welcome"}

How element targeting works

inspect_screen returns a compact tree where every node has a stable id derived from its semantic identity (resource-id / accessibility / class + digit-normalized text), not its position. So a counter ticking from 5 to 6 keeps its id and shows up as a changed node in a diff, while a newly-appeared element is added. Act tools accept that id, a text/resource-id selector, or raw coordinates; when you use a selector, the recorded flow stores the selector (resilient replay) rather than brittle coordinates.

Performance

Hierarchy reads use a three-tier backend, chosen per device:

1. adb uiautomator dump (~2.5s, no extra process) — the default on Android. Tried first.
2. Warm hierarchy engine — when uiautomator can't reach UI-idle (e.g. apps with constant animations/watermarks, where uiautomator dump errors with could not get idle state), manos keeps one long-lived maestro mcp child resident (used under the hood) and reuses its connected driver. First call pays a one-time warm-up; subsequent inspects are ~150–300ms — the payoff of reusing a resident engine instead of cold-starting the JVM per call.
3. Cold maestro hierarchy CLI — last resort if the warm session can't start.

Once a device needs the warm session, manos remembers it (per-device) so it doesn't re-pay the uiautomator timeout on every inspect. Screen size/density are cached. The warm child (and its simulator-server) are killed via a process-tree cleanup on exit.

Measured on a hard case (an app that never idles, so everything routes through the warm session):

So: on apps where uiautomator works, the adb path is fast with no extra process; on apps that force the fallback, the resident warm engine keeps steady-state inspect in the ~175ms range, and the act+observe loop avoids the per-action JVM cold-start that made it slow before. The remaining first-call cost is the one-time uiautomator probe before switching to warm.

Architecture

src/
  cli.ts                 serve / doctor / devices
  server.ts              McpServer wiring (stdio)
  tools/
    register.ts          all 39 tools
    context.ts           shared state: resolveTarget + act/observe + last-screen cache
  drivers/
    types.ts             Driver contract + Capability model
    android.ts           adb
    ios.ts               simctl + idb (+ maestro fallback)
    registry.ts          device → driver routing
  core/
    hierarchy.ts         compact JSON, stable ids, screen diff, search
    a11y.ts              accessibility heuristics
    waits.ts             condition polling
    session.ts           action journal
    flow.ts              Maestro-flow emitter
    maestro.ts           maestro CLI passthrough (run_flow, cheat sheet)
    maestroDriver.ts     cold maestro hierarchy + one-shot action fallbacks
    maestroSession.ts    warm long-lived `maestro mcp` backend (fast hierarchy/actions)
    netcapture.ts        network capture (Frida OkHttp / mitmproxy) — see NETWORK.md
    ocr.ts               OCR fallback (Apple Vision / Tesseract) for off-tree elements
  assets/frida/          okhttp-capture.js + sidecar.py (injected by netcapture)
  util/                  exec + toolchain discovery

Each driver method may throw a CapabilityError; tools surface it as an actionable message instead of an opaque subprocess failure. The capability model is reported live so an agent can check support before relying on a platform-specific action.

Test

npm test    # unit tests for hierarchy/diff/a11y/flow (no device needed)

The hierarchy parsing, stable-id diffing, accessibility math, screenshot capture, log/crash scan, and the recording→export_flow→maestro check-syntax pipeline have also been verified end-to-end against a live Android emulator.

License

MIT