TouchBridge

TouchBridge is a local-first MCP server for iOS simulators and physical devices. It gives ChatGPT, Codex, Claude, Cursor, and other MCP hosts a reliable action layer for app testing—and a structured screenshot bridge for voice-driven design work.

The design workflow is the unusual bit: “capture this screen for editing” produces a full-resolution image, redacted accessibility geometry, normalized editor layers, the sanitized spoken instruction, a preview, and a versioned manifest. An orchestrating agent can reconstruct the screen in Figma without reverse-engineering the raw accessibility tree.

Why TouchBridge

• One tool surface for simulators and real iPhones.

• Active-device filtering avoids stale, paired, or disconnected hardware.

• Sensitive text is redacted from tool results, logs, and design artifacts.

• Durable design snapshots are useful beyond a single agent session.

• editor.json provides named layers, normalized frames, interactivity, image scale, and Figma styling hints.

• A loopback-only live viewer never binds to the public network.

• doctor diagnoses the entire local toolchain in one call.

• CI covers Node 20.17 and Node 22, with no production audit findings.

Related MCP server: Simulator MCP

Voice-to-design loop

flowchart LR
  V["Voice request"] --> H["ChatGPT / Codex / Claude"]
  H --> T["TouchBridge"]
  T --> I["iPhone or Simulator"]
  T --> S["PNG + redacted UI map + manifest"]
  S --> F["Figma / Slides / image editor"]
  F --> H
  H --> T

MCP servers do not need to call one another or share credentials. The host agent coordinates TouchBridge and the design tool.

Capabilities

Requirements

• macOS

• Xcode command-line tools

• Node.js 20.17 or newer

• Homebrew

• Developer Mode and trust pairing for a physical iPhone/iPad

Run from source

git clone https://github.com/MarshallBear1/touchbridge-mcp.git
cd touchbridge-mcp
npm install
npm run check
npm link
touchbridge --setup-all

Restart the MCP host, boot a simulator or connect an unlocked device, then ask:

Run TouchBridge doctor, find my active iPhone, and test the login flow.

Or:

Capture the current screen for editing, reconstruct the interactive regions in Figma,
and label anything that fails accessibility checks.

MCP tools

See the snapshot contract and the orchestration architecture.

Local data and security

TouchBridge stores its state beneath ~/.touchbridge/.

~/.touchbridge/
├── captures/       durable design handoffs
├── python/         isolated idb environment
├── idb-companion/  local companion support
├── wda-build/      WebDriverAgent source and build data
└── bin/            native accessibility helper

• The live viewer listens on 127.0.0.1 only.

• Capture names are sanitized and cannot escape the capture directory.

• Password, passcode, PIN, OTP, verification-code, secret, and API-key fields are redacted.

• Text input values are never echoed in MCP results or logs.

• TouchBridge stores no Figma, ChatGPT, Claude, or other third-party credentials.

Development

npm install
npm run typecheck
npm test
npm run check
npm pack --dry-run

CI runs the full check on macOS with Node 20.17 and Node 22.

Roadmap

• Semantic element targeting (tap "Continue" without manual coordinates)

• Screenshot diffing and visual-regression baselines

• Session recording and replayable test scripts

• Editable Figma reconstruction with component matching

• Voice interruption, confirmation, and undo policies

• Multi-device test matrices

• Pluggable privacy policies for regulated apps

License and attribution

TouchBridge is MIT licensed. It includes work derived from the MIT-licensed iPhone-mcp project; the required upstream copyright notice is preserved in LICENSE, with provenance in NOTICE.md.