[Bug]: stop_mac_app with appName kills unrelated processes due to pkill -f

[ryotapoi]

Bug Description

When stop_mac_app is called with appName, it uses pkill -f (substring match on the full command line), which sends SIGTERM to unrelated processes whose command line happens to contain the app name.

Debug Output

XcodeBuildMCP Doctor

Generated: 2026-04-03T11:57:07.527Z
Server Version: 2.3.2
Output Mode: ⚠️ Non-redacted (opt-in)

## System Information
- platform: darwin
- release: 25.4.0
- arch: arm64
- cpus: 14 x Apple M4 Pro
- memory: 48 GB
- hostname: mbp-m4.local
- username: ryota
- homedir: /Users/ryota
- tmpdir: /var/folders/1y/l1zx_f3n7s987jz5n6hhfd2c0000gn/T

## Node.js Information
- version: v25.6.0
- execPath: /opt/homebrew/Cellar/node/25.6.0/bin/node
- pid: 74395
- ppid: 74301
- platform: darwin
- arch: arm64
- cwd: /Users/ryota/Sources/ryotapoi/Brimday/.claude/worktrees/cross_block_drag
- argv: /opt/homebrew/Cellar/node/25.6.0/bin/node /Users/ryota/.npm/_npx/99336612077b7094/node_modules/.bin/xcodebuildmcp mcp

## Process Tree
- Running under Xcode: ❌ No
- 74395 (ppid 74301): node — node /Users/ryota/.npm/_npx/99336612077b7094/node_modules/.bin/xcodebuildmcp mcp
- 74301 (ppid 74287): npm — exec xcodebu npm exec xcodebuildmcp@latest mcp
- 74287 (ppid 57325): claude — claude --append-system-prompt-file /Users/ryota/.claude/resources/rules/personality.md --resume eaef67d1-ebc8-47de-9dcb-bd35f6d5b185
- 57325 (ppid 5714): -zsh — -zsh
- 5714 (ppid 1): tmux — tmux new -s SKM
- 1 (ppid 0): /sbin/launchd — /sbin/launchd

## Xcode Information
- version: Xcode 26.4 - Build version 17E192
- path: /Applications/Xcode-26.4.0.app/Contents/Developer
- selectedXcode: /Applications/Xcode-26.4.0.app/Contents/Developer/usr/bin/xcodebuild
- xcrunVersion: xcrun version 72.

## Dependencies
- axe: ✅ v1.5.2
- mise: ❌ Not found

## Environment Variables
- INCREMENTAL_BUILDS_ENABLED: (not set)
- DEVELOPER_DIR: (not set)
- HOME: /Users/ryota
- USER: ryota
- TMPDIR: /var/folders/1y/l1zx_f3n7s987jz5n6hhfd2c0000gn/T/
- NODE_ENV: (not set)
- SENTRY_DISABLED: (not set)
- AXE_PATH: (not set)
- XBMCP_LAUNCH_JSON_WAIT_MS: (not set)
- XCODEBUILDMCP_DEBUGGER_BACKEND: (not set)
- XCODEBUILDMCP_UI_DEBUGGER_GUARD_MODE: (not set)
- XCODEBUILDMCP_DEBUG: true
- XCODEBUILDMCP_RUNTIME: mcp
- XCODEBUILDMCP_SILENCE_LOGS: true

## Feature Status

### UI Automation (axe)
- Available: ✅ Yes
- UI Automation Supported: ✅ Yes
- Simulator Video Capture Supported (AXe >= 1.1.0): ✅ Yes
- UI-Debugger Guard Mode: error

### Incremental Builds
- Enabled: ❌ No
- xcodemake Binary Available: ❌ No
- Makefile exists (cwd): (not checked: incremental builds disabled)

### Mise Integration
- Running under mise: ❌ No
- Mise available: ❌ No

### Debugger Backend (DAP)
- lldb-dap available: ✅ Yes
- Selected backend: dap

### Manifest Tool Inventory
- Total Unique Tools: 82
- Workflow Count: 16
- coverage: 2 tools
- debugging: 8 tools
- device: 17 tools
- doctor: 1 tools
- logging: 4 tools
- macos: 13 tools
- project-discovery: 5 tools
- project-scaffolding: 2 tools
- session-management: 5 tools
- simulator-management: 8 tools
- simulator: 23 tools
- swift-package: 8 tools
- ui-automation: 11 tools
- utilities: 1 tools
- workflow-discovery: 1 tools
- xcode-ide: 5 tools

### Runtime Tool Registration
- Enabled Workflows: 4
- Registered Tools: 35
- Workflows: doctor, macos, session-management, simulator

### Xcode IDE Bridge (mcpbridge)
- Workflow enabled: ❌ No
- mcpbridge path: /Applications/Xcode-26.4.0.app/Contents/Developer/usr/bin/mcpbridge
- Xcode running: true
- Connected: ❌ No
- Bridge PID: (none)
- Proxied tools: 0
- Last error: (none)
- Note: Bridge debug tools (status/sync/disconnect) are only registered when debug: true

## Tool Availability Summary
- Build Tools: ✅ Available
- UI Automation Tools: ✅ Available
- Incremental Build Support: ❌ Not available

## Sentry
- Sentry enabled: ✅ Yes

Editor/Client

Claude Code

MCP Server Version

2.3.2

LLM

Claude Opus 4.6

Steps to Reproduce

1. Create a tmux session with the same name as the app: tmux new -s Brimday
2. Launch Claude Code inside that tmux session
3. Build and launch a macOS app via build_run_macos
4. Stop the app via stop_mac_app({ appName: "Brimday" })
5. The tmux client is killed and the session is detached

Expected Behavior

Only the target application process should be terminated. Alternatively, build_run_macos / launch_mac_app should return a processId so that stop_mac_app can be called with processId to terminate only the specific process.

Actual Behavior

pkill -f "Brimday" matches the tmux client process (whose command line contains the session name "Brimday") and kills it. The tmux server survives so tmux a can reconnect, but the workflow is interrupted. Using processId instead of appName does not cause this issue.