xcforge MCP server

xcforge

An MCP server and CLI for iOS development — build, test, automate, and diagnose from any AI agent or terminal.

104 MCP tools. 19 CLI command groups. Single native binary (~8 MB stripped, ~18 MB with debug symbols). Zero external runtime dependencies.

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Install

Homebrew (recommended)

brew tap justinthevoid/tap && brew install xcforge

Claude Code (one-liner)

claude mcp add xcforge -- xcforge

This registers xcforge as an MCP server in your current project. Run it after installing via Homebrew.

From source

git clone https://github.com/justinthevoid/xcforge.git
cd xcforge && swift build -c release
cp .build/release/XCForgeCLI /usr/local/bin/xcforge

Uninstall

Homebrew

brew uninstall xcforge
brew untap justinthevoid/tap   # optional: remove the tap

From source

rm /usr/local/bin/xcforge

Remove MCP configuration

After uninstalling the binary, remove the "xcforge" entry from your MCP client config file (see Configure for file locations).

For Claude Code:

claude mcp remove xcforge

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Configure

Add xcforge to your MCP client. Each client has a different config format and file location.

Claude Code

The fastest way is the CLI command shown above under Install. To configure manually, add to .mcp.json in your project root (or ~/.claude/.mcp.json for global):

{
  "mcpServers": {
    "xcforge": {
      "command": "xcforge",
      "args": [],
      "type": "stdio"
    }
  }
}

Claude Desktop

File: ~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "xcforge": {
      "command": "/opt/homebrew/bin/xcforge",
      "args": []
    }
  }
}

Note: Claude Desktop does not inherit your shell PATH. Use the full Homebrew path — /opt/homebrew/bin/xcforge on Apple Silicon, /usr/local/bin/xcforge on Intel.

Cursor

File: .cursor/mcp.json in your project root (or ~/.cursor/mcp.json for global)

{
  "mcpServers": {
    "xcforge": {
      "command": "/opt/homebrew/bin/xcforge",
      "args": []
    }
  }
}

Note: Same PATH caveat as Claude Desktop — use the absolute path. Restart Cursor after changes.

VS Code (GitHub Copilot)

File: .vscode/mcp.json in your project root

{
  "servers": {
    "xcforge": {
      "command": "xcforge",
      "args": [],
      "type": "stdio"
    }
  }
}

Note: VS Code uses "servers" not "mcpServers". Requires the GitHub Copilot extension with agent mode enabled. VS Code typically resolves PATH from your shell, so the bare command works.

Windsurf

File: ~/.codeium/windsurf/mcp_config.json

{
  "mcpServers": {
    "xcforge": {
      "command": "/opt/homebrew/bin/xcforge",
      "args": []
    }
  }
}

Note: Full path recommended. Restart Windsurf after editing.

Zed

File: ~/.config/zed/settings.json (or .zed/settings.json per-project)

{
  "context_servers": {
    "xcforge": {
      "command": {
        "path": "/opt/homebrew/bin/xcforge",
        "args": []
      },
      "settings": {}
    }
  }
}

Note: Zed uses "context_servers" with a nested "command.path" — different from every other client.

Config quick reference

Client	Config key	File location	Needs absolute path?
Claude Code	mcpServers	.mcp.json	No
Claude Desktop	mcpServers	~/Library/Application Support/Claude/claude_desktop_config.json	Yes
Cursor	mcpServers	.cursor/mcp.json	Yes
VS Code	servers	.vscode/mcp.json	No
Windsurf	mcpServers	~/.codeium/windsurf/mcp_config.json	Yes
Zed	context_servers	~/.config/zed/settings.json	Yes

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Claude Code Skill

xcforge ships an agent skill: the tool reference an agent loads when it works on iOS tasks. The binary carries it, so installing it needs nothing else:

xcforge skill install            # this repo: .claude/skills/xcforge (commit it to share with the team)
xcforge skill install --global   # every project: ~/.claude/skills/xcforge
xcforge skill install --dir <skills-dir>      # any other agent's skills directory
xcforge skill status             # where it's installed and whether it matches this xcforge
xcforge skill show references/test-tools.md   # print one file without installing

Re-run xcforge skill install after upgrading xcforge to refresh the copy; only changed files are rewritten. It won't overwrite an xcforge skill directory it didn't create unless you pass --force. xcforge skill uninstall removes it.

Once installed, Claude will automatically load the right reference files when you use xcforge tools — exact parameters, return values, and usage patterns for each category (build, test, simulator, UI automation, logs, LLDB, diagnosis, and more).

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Two Modes, Same Tools

xcforge                          # MCP server (stdio JSON-RPC, 104 tools)
xcforge build --scheme MyApp     # CLI mode (19 command groups)

Every tool available over MCP has a matching CLI command. Every CLI command supports --json.

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Tools Overview

Category	Count	Highlights
Build	6	build_sim, build_compile (fast compile-only), build_run_sim, clean, project/scheme discovery
Test	7	test_sim with xcresult parsing, test_failures, test_coverage, list_tests, test_plan_inspect, agent output mode, known-failures gating
Simulator	18	Full lifecycle + video recording, location simulation, dark mode toggle, status bar override, info
Physical Devices	10	Via devicectl — list, install, launch (deep links, env), screenshot, WebDriverAgent on device
UI Automation	20	WebDriverAgent + native AX bridge — find, tap (point or pixel), swipe, drag, type, alerts
Screenshots	3	Framebuffer capture (0.3s), point-space coordinate alignment, optional grid overlay
Visual Regression	3	Pixel-diff baselines, multi-device checks (Dark Mode, Landscape, iPad), bless workflow
Logs	4	4-layer filtered capture, 8 topic categories, regex wait
Console	3	stdout/stderr capture for launched apps
SPM	5	Resolve, update, show deps, reset, clean
Accessibility	5	Audit labels, traits, VoiceOver order, contrast
Git	5	Status, diff, log, commit, branch
LLDB Debugger	8	Attach, breakpoints, inspect variables, backtrace, step/continue, arbitrary commands
Diagnosis	10	Multi-step workflows: build, run, inspect, capture evidence, compare, verify
Plan Execution	2	Scripted multi-step automation with assertions
Session	3	Persistent defaults, .xcforge.yaml repo config, session profiles

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Key Capabilities

Structured Test Results

Test output is parsed from .xcresult bundles — the structured format Xcode generates internally — not from raw xcodebuild stdout/stderr.

A single test_sim call returns: pass/fail counts, failure messages with source location, exported failure screenshots, and the xcresult path for deeper inspection via test_failures or test_coverage.

Fast Screenshots

The screenshot tool reads the simulator framebuffer via CoreSimulator's IOSurface API, falling back to ScreenCaptureKit, then simctl. Typical latency is ~300ms.

UI Automation Without Appium

xcforge communicates directly with WebDriverAgent over HTTP and supplements it with a native Accessibility API bridge (AXPBridge). This means:

• find_element with scroll: true auto-scrolls using 3 fallback strategies
• handle_alert searches across SpringBoard, ContactsUI, and the active app — accept_all clears multiple permission dialogs in one call
• drag_and_drop works with element IDs, not just coordinates
• get_source returns the full view hierarchy in ~20ms

Topic-Filtered Logs

start_log_capture streams os_log through 4 filter layers:

1. Noise exclusion — strips 15 known noisy processes at the stream level
2. Capture modes — smart (broad + topic-ready), app (tight, auto-detected bundle), verbose
3. Topic filtering — read_logs classifies lines into 8 topics (app, crashes, network, lifecycle, springboard, widgets, background, system) and shows only app + crashes by default
4. Deduplication — collapses repeated lines

The response includes a topic menu with counts, so the agent can pull in specific topics on demand without re-querying.

Interactive LLDB Debugger

8 tools for attaching LLDB to running simulator processes, setting breakpoints, inspecting variables, viewing stack traces, and stepping through code. Sessions persist for 30 minutes, so you can attach once and run multiple debugging operations. CLI commands are one-shot (attach → operation → detach). Includes:

• Session management: lldb_attach (by bundle ID or PID), lldb_detach
• Breakpoints: set by file+line or function name, remove by ID
• Inspection: evaluate expressions at the current frame, view stack traces
• Execution control: continue, step over, step into, step out (with 10-second timeout)
• Raw passthrough: run arbitrary LLDB commands

Use alongside logs and screenshots for systematic root-cause analysis.

Diagnosis Workflows

10 tools (off by default: turn them on with XCFORGE_TOOL_GROUPS=+diagnose or tool_groups) that chain together into structured diagnostic pipelines — start a session, build, launch, capture runtime signals, collect evidence (screenshots, logs, accessibility state), compare against previous runs, and verify fixes. Designed for agents to systematically debug issues across multiple iterations.

Physical Device Support

Tools wrapping Apple's devicectl for real devices: list connected devices, install, launch (with deep links and environment variables) and terminate apps, and take screenshots. xcforge wda start --device <udid> --team <TEAM> (MCP wda_start) builds, signs and starts WebDriverAgent on the device so the UI automation tools work there too; see device-tools.md.

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CLI Examples

xcforge init                                     # Scaffold a committed .xcforge.yaml (repo defaults)
xcforge build                                    # Build (auto-detects project, scheme, sim)
xcforge build compile --scheme MyApp             # Fast compile-only check (~5s)
xcforge build --scheme MyApp --simulator "iPhone 16 Pro"
xcforge test --scheme MyApp --json               # Run tests, JSON output
xcforge test --for agent                         # Agent-optimized slim JSON
xcforge test --gate                              # Subtract known-failures.yaml
xcforge test rerun-failed                        # Replay last run's failures
xcforge test plan inspect --plan AllTests        # Inspect .xctestplan
xcforge build-test --env BLESS_BASELINE=1        # Inject env var into test process
xcforge test failures --xcresult /path/to.xcresult
xcforge test coverage --min-coverage 80
xcforge bless --baseline login --tests "UITests/LoginTests"  # Baseline+test+diff in one call
xcforge sim list                                 # List simulators
xcforge sim boot "iPhone 16 Pro"
xcforge sim info                                 # Booted simulator screen size and scale
xcforge ui find --aid "loginButton"              # Find by accessibility ID
xcforge ui tap --element el-0                    # Tap element at point coordinates
xcforge ui tap-pixel --x 750 --y 1334            # Tap at pixel coordinates
xcforge screenshot                               # Screenshot to stdout
xcforge screenshot --grid --output /tmp/x.png    # Screenshot with point-coordinate grid
xcforge pose Settings                            # Build, install, launch to a screen
xcforge log start                                # Start log capture
xcforge log read --include network               # Read with topic filter
xcforge spm resolve                              # Resolve packages
xcforge device list                              # Connected physical devices
xcforge debug attach --bundle-id com.example.App    # Attach debugger
xcforge debug breakpoint set --bundle-id com.example.App --file ViewController.swift --line 42
xcforge debug inspect --bundle-id com.example.App --expression "self.count"
xcforge debug backtrace --bundle-id com.example.App # Show stack trace
xcforge debug continue --bundle-id com.example.App --mode step-over
xcforge diagnose start --scheme MyApp            # Start diagnosis session

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Alternatives

There are several iOS-focused MCP servers worth knowing about:

Server	Stars	Scope	Build	Test	UI Automation	Screenshots	Visual Regression	Accessibility	Physical Devices	SPM	Git	Logs
xcforge	—	104 tools	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
XcodeBuildMCP	~5k	~15 tools	Yes	Yes	Partial	No	No	No	No	No	No	No
ios-simulator-mcp	~1.8k	~10 tools	No	No	Yes	Yes	No	No	No	No	No	No
xcode-mcp-server	~370	~8 tools	Partial	No	No	No	No	No	No	No	No	No
iosef	<10	~5 tools	No	No	Yes	No	No	No	No	No	No	No
Appium MCP	<50	~10 tools	No	No	Yes	Yes	No	No	Partial	No	No	No

• XcodeBuildMCP — The most popular iOS MCP server. Backed by Sentry. Covers build, test, and simulator management well. If you only need build/run workflows, it's a solid choice.
• ios-simulator-mcp — Focused on simulator UI interaction — screenshots, taps, swipes, accessibility tree. Good if you only need simulator automation.
• xcode-mcp-server — Early MCP server for Xcode project management. Basic integration — no simulator automation, testing, or device support.
• iosef — Agent-optimized simulator CLI with clean ergonomics. Narrow scope but thoughtful design. Swift native.
• Appium MCP — Cross-platform (iOS + Android) via the Appium ecosystem. Requires Node.js + Java + Appium server — heavier dependency chain.

Where xcforge fits: It combines fast compile checks, build, test, pixel-accurate UI automation, screenshot grids, screen-targeted launch, log analysis, visual regression, device support, SPM, accessibility auditing, and multi-step diagnosis in a single zero-dependency binary. The trade-off is iOS-only — no Android, watchOS, or visionOS.

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UI Automation Setup

UI automation tools require a WebDriverAgent (WDA) backend running on the simulator. xcforge manages the WDA connection automatically — you just need to point it at a WDA project.

xcforge tries two backends in order:

1. xcforgeWDA (preferred) — xcforge's own WDA fork (com.xcforge.wda.runner). Auto-built and deployed when XCFORGE_WDA_DIR is set.
2. Original WebDriverAgent (fallback) — Facebook/Appium's WDA. Picked up automatically if WDA is already running on port 8100.

Quick setup

Clone appium/WebDriverAgent, rename the project and scheme for xcforge, then set XCFORGE_WDA_DIR:

git clone https://github.com/appium/WebDriverAgent.git xcforgeWDA

# Copy project with xcforge name and remap bundle ID
cp -r xcforgeWDA/WebDriverAgent.xcodeproj xcforgeWDA/xcforgeWDA.xcodeproj
sed -i '' 's/com\.facebook\.WebDriverAgentRunner/com.xcforge.wda.runner/g' \
  xcforgeWDA/xcforgeWDA.xcodeproj/project.pbxproj

# Add xcforgeWDARunner scheme
cp xcforgeWDA/xcforgeWDA.xcodeproj/xcshareddata/xcschemes/WebDriverAgentRunner.xcscheme \
   xcforgeWDA/xcforgeWDA.xcodeproj/xcshareddata/xcschemes/xcforgeWDARunner.xcscheme
sed -i '' 's/WebDriverAgent\.xcodeproj/xcforgeWDA.xcodeproj/g' \
  xcforgeWDA/xcforgeWDA.xcodeproj/xcshareddata/xcschemes/xcforgeWDARunner.xcscheme

Then add XCFORGE_WDA_DIR to your MCP config:

{
  "mcpServers": {
    "xcforge": {
      "command": "xcforge",
      "env": {
        "XCFORGE_WDA_DIR": "/path/to/xcforgeWDA"
      }
    }
  }
}

xcforge builds and deploys WDA automatically on the first UI tool call on a simulator (~30–60s on first run, instant thereafter). For a physical device run xcforge wda start --device <udid> --team <TEAM> (MCP wda_start) first, with the device unlocked and Settings > Developer > Enable UI Automation on. See the full UI Automation Setup guide for alternative configurations, custom ports, and troubleshooting.

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Requirements

• macOS 13+
• Xcode 15+
• Swift 6.0+ (source builds only)
• WebDriverAgent (UI automation only — see UI Automation Setup)

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Web Baseline (Story 1.1)

The Web workspace is isolated under Web/ and uses Astro Starlight plus Svelte with Bun-only package/script usage and Biome-only lint/format checks.

cd Web
bun install
bun run typecheck
bun run lint
bun run validate

Local route assumptions after bun run dev:

• Marketing route: http://localhost:4321/
• Docs route: http://localhost:4321/docs
• Docs depth route: http://localhost:4321/docs/getting-started

If setup fails, run:

cd Web
bun run doctor

Remediation steps are documented in Web/README.md.

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Support

If xcforge saves you time, consider supporting development:

License

MIT — see LICENSE.

Contributing

Issues and PRs welcome. See CONTRIBUTING.md.