diff --git a/electron/main.ts b/electron/main.ts
index 1165a590..76ededff 100644
--- a/electron/main.ts
+++ b/electron/main.ts
@@ -484,27 +484,54 @@ function findGitBashSync(): boolean {
  */
 function getExpandedShellPath(): string {
   const home = os.homedir();
-  const shellPath = userShellEnv.PATH || process.env.PATH || '';
+  const shellEnv = { ...process.env, ...userShellEnv };
+  const shellPath = shellEnv.PATH || process.env.PATH || '';
   const sep = path.delimiter;
-
-  if (process.platform === 'win32') {
-    const appData = process.env.APPDATA || path.join(home, 'AppData', 'Roaming');
-    const localAppData = process.env.LOCALAPPDATA || path.join(home, 'AppData', 'Local');
-    const winExtra = [
-      path.join(appData, 'npm'),
-      path.join(localAppData, 'npm'),
-      path.join(home, '.npm-global', 'bin'),
-      path.join(home, '.local', 'bin'),
-      path.join(home, '.claude', 'bin'),
-    ];
-    const allParts = [shellPath, ...winExtra].join(sep).split(sep).filter(Boolean);
-    return [...new Set(allParts)].join(sep);
-  } else {
-    const basePath = `/usr/local/bin:/opt/homebrew/bin:/usr/bin:/bin`;
-    const raw = `${basePath}:${home}/.npm-global/bin:${home}/.local/bin:${home}/.claude/bin:${shellPath}`;
-    const allParts = raw.split(':').filter(Boolean);
-    return [...new Set(allParts)].join(':');
-  }
+  const pnpmHome = shellEnv.PNPM_HOME;
+  const voltaHome = shellEnv.VOLTA_HOME ? path.join(shellEnv.VOLTA_HOME, 'bin') : '';
+
+  const extraDirs = process.platform === 'win32'
+    ? [
+        path.join(home, '.local', 'bin'),
+        path.join(home, '.claude', 'bin'),
+        path.join(home, '.claude', 'local'),
+        path.join(home, '.bun', 'bin'),
+        path.join(home, '.yarn', 'bin'),
+        path.join(home, '.config', 'yarn', 'global', 'node_modules', '.bin'),
+        voltaHome,
+        path.join(home, '.fnm', 'current', 'bin'),
+        path.join(home, '.nvm', 'current', 'bin'),
+        path.join(home, '.asdf', 'shims'),
+        path.join(shellEnv.APPDATA || path.join(home, 'AppData', 'Roaming'), 'npm'),
+        path.join(shellEnv.LOCALAPPDATA || path.join(home, 'AppData', 'Local'), 'npm'),
+        path.join(shellEnv.APPDATA || path.join(home, 'AppData', 'Roaming'), 'pnpm'),
+        path.join(shellEnv.LOCALAPPDATA || path.join(home, 'AppData', 'Local'), 'pnpm'),
+        pnpmHome,
+        path.join(home, '.npm-global', 'bin'),
+      ]
+    : [
+        path.join(home, '.local', 'bin'),
+        path.join(home, '.claude', 'bin'),
+        path.join(home, '.claude', 'local'),
+        path.join(home, '.bun', 'bin'),
+        '/opt/homebrew/bin',
+        '/usr/local/bin',
+        '/usr/bin',
+        '/bin',
+        path.join(home, '.npm-global', 'bin'),
+        path.join(home, '.yarn', 'bin'),
+        path.join(home, '.config', 'yarn', 'global', 'node_modules', '.bin'),
+        path.join(home, '.volta', 'bin'),
+        path.join(home, '.fnm', 'current', 'bin'),
+        path.join(home, '.nvm', 'current', 'bin'),
+        path.join(home, '.asdf', 'shims'),
+        pnpmHome,
+        path.join(home, '.local', 'share', 'pnpm'),
+        ...(process.platform === 'darwin' ? [path.join(home, 'Library', 'pnpm')] : []),
+      ];
+
+  const allParts = [shellPath, ...extraDirs].join(sep).split(sep).filter(Boolean);
+  return [...new Set(allParts)].join(sep);
 }
 
 function getPort(): Promise<number> {
@@ -770,34 +797,70 @@ app.whenReady().then(async () => {
   ipcMain.handle('install:check-prerequisites', async () => {
     const expandedPath = getExpandedShellPath();
     const execEnv = { ...sanitizedProcessEnv(), ...userShellEnv, PATH: expandedPath };
+    const shellEnv = { ...process.env, ...userShellEnv };
 
     // Candidate paths — native first, then bun, then homebrew, then npm
     const home = os.homedir();
-    const candidatePaths = process.platform === 'win32'
+    const claudeSearchDirs = process.platform === 'win32'
       ? [
-          path.join(home, '.local', 'bin', 'claude.exe'),
-          path.join(home, '.local', 'bin', 'claude.cmd'),
-          path.join(home, '.claude', 'bin', 'claude.exe'),
-          path.join(home, '.claude', 'bin', 'claude.cmd'),
-          path.join(home, '.bun', 'bin', 'claude.exe'),
-          path.join(home, '.bun', 'bin', 'claude.cmd'),
-          path.join(process.env.APPDATA || '', 'npm', 'claude.cmd'),
-          path.join(process.env.LOCALAPPDATA || '', 'npm', 'claude.cmd'),
-        ].filter(p => p && !p.startsWith(path.sep))
+          path.join(home, '.local', 'bin'),
+          path.join(home, '.claude', 'bin'),
+          path.join(home, '.claude', 'local'),
+          path.join(home, '.bun', 'bin'),
+          path.join(home, '.yarn', 'bin'),
+          path.join(home, '.config', 'yarn', 'global', 'node_modules', '.bin'),
+          shellEnv.VOLTA_HOME ? path.join(shellEnv.VOLTA_HOME, 'bin') : '',
+          path.join(home, '.fnm', 'current', 'bin'),
+          path.join(home, '.nvm', 'current', 'bin'),
+          path.join(home, '.asdf', 'shims'),
+          path.join(shellEnv.APPDATA || path.join(home, 'AppData', 'Roaming'), 'npm'),
+          path.join(shellEnv.LOCALAPPDATA || path.join(home, 'AppData', 'Local'), 'npm'),
+          path.join(shellEnv.APPDATA || path.join(home, 'AppData', 'Roaming'), 'pnpm'),
+          path.join(shellEnv.LOCALAPPDATA || path.join(home, 'AppData', 'Local'), 'pnpm'),
+          shellEnv.PNPM_HOME || '',
+          path.join(home, '.npm-global', 'bin'),
+        ]
       : [
-          path.join(home, '.local', 'bin', 'claude'),
-          path.join(home, '.claude', 'bin', 'claude'),
-          path.join(home, '.bun', 'bin', 'claude'),
-          '/opt/homebrew/bin/claude',
-          '/usr/local/bin/claude',
-          path.join(home, '.npm-global', 'bin', 'claude'),
+          path.join(home, '.local', 'bin'),
+          path.join(home, '.claude', 'bin'),
+          path.join(home, '.claude', 'local'),
+          path.join(home, '.bun', 'bin'),
+          '/opt/homebrew/bin',
+          '/usr/local/bin',
+          path.join(home, '.npm-global', 'bin'),
+          path.join(home, '.yarn', 'bin'),
+          path.join(home, '.config', 'yarn', 'global', 'node_modules', '.bin'),
+          path.join(home, '.volta', 'bin'),
+          path.join(home, '.fnm', 'current', 'bin'),
+          path.join(home, '.nvm', 'current', 'bin'),
+          path.join(home, '.asdf', 'shims'),
+          shellEnv.PNPM_HOME || '',
+          path.join(home, '.local', 'share', 'pnpm'),
+          ...(process.platform === 'darwin' ? [path.join(home, 'Library', 'pnpm')] : []),
         ];
 
+    const candidatePaths = process.platform === 'win32'
+      ? [...new Set(claudeSearchDirs.filter(Boolean).flatMap(dir => [
+          path.join(dir, 'claude.exe'),
+          path.join(dir, 'claude.cmd'),
+          path.join(dir, 'claude.bat'),
+          path.join(dir, 'claude'),
+        ]))]
+      : [...new Set(claudeSearchDirs.filter(Boolean).map(dir => path.join(dir, 'claude')))];
+
     function classifyPath(p: string): 'native' | 'homebrew' | 'npm' | 'bun' | 'unknown' {
       const n = p.replace(/\\/g, '/');
-      if (n.includes('/.local/bin/') || n.includes('/.claude/bin/')) return 'native';
+      if (n.includes('/.local/bin/') || n.includes('/.claude/bin/') || n.includes('/.claude/local/')) return 'native';
       if (n.includes('/.bun/bin/') || n.includes('/.bun/install/')) return 'bun';
       if (n.includes('/homebrew/') || n.includes('/Cellar/')) return 'homebrew';
+      if (n.includes('/Library/pnpm/')
+        || n.includes('/.local/share/pnpm/')
+        || n.includes('/.config/yarn/')
+        || n.includes('/.yarn/bin/')
+        || n.includes('/.volta/bin/')
+        || n.includes('/.fnm/current/bin/')
+        || n.includes('/.asdf/shims/')
+        || n.includes('/.nvm/current/bin/')) return 'npm';
       if (n.includes('/npm')) return 'npm';
       if (n === '/usr/local/bin/claude') {
         try {
@@ -808,6 +871,14 @@ app.whenReady().then(async () => {
         } catch { /* ignore */ }
         return 'unknown';
       }
+      if (process.platform === 'win32') {
+        const appData = (shellEnv.APPDATA || '').replace(/\\/g, '/');
+        const localAppData = (shellEnv.LOCALAPPDATA || '').replace(/\\/g, '/');
+        if (appData && n.startsWith(appData + '/npm')) return 'npm';
+        if (localAppData && n.startsWith(localAppData + '/npm')) return 'npm';
+        if (appData && n.startsWith(appData + '/pnpm')) return 'npm';
+        if (localAppData && n.startsWith(localAppData + '/pnpm')) return 'npm';
+      }
       return 'unknown';
     }
 
diff --git a/src/__tests__/unit/platform-claude-paths.test.ts b/src/__tests__/unit/platform-claude-paths.test.ts
new file mode 100644
index 00000000..7a17c394
--- /dev/null
+++ b/src/__tests__/unit/platform-claude-paths.test.ts
@@ -0,0 +1,64 @@
+import { describe, it } from 'node:test';
+import assert from 'node:assert/strict';
+
+import { getClaudeCandidatePathsFor, getExtraPathDirsFor } from '../../lib/platform';
+
+describe('Claude path discovery helpers', () => {
+  it('darwin search dirs include pnpm, yarn, and claude local compatibility paths', () => {
+    const home = '/Users/tester';
+    const dirs = getExtraPathDirsFor('darwin', home, {
+      PNPM_HOME: '/Users/tester/Library/pnpm',
+    } as unknown as NodeJS.ProcessEnv);
+
+    assert.ok(dirs.includes('/Users/tester/Library/pnpm'));
+    assert.ok(dirs.includes('/Users/tester/.claude/local'));
+    assert.ok(dirs.includes('/Users/tester/.yarn/bin'));
+  });
+
+  it('darwin candidates include executable paths for pnpm and claude local wrappers', () => {
+    const home = '/Users/tester';
+    const candidates = getClaudeCandidatePathsFor('darwin', home, {
+      PNPM_HOME: '/Users/tester/Library/pnpm',
+    } as unknown as NodeJS.ProcessEnv);
+
+    assert.ok(candidates.includes('/Users/tester/Library/pnpm/claude'));
+    assert.ok(candidates.includes('/Users/tester/.claude/local/claude'));
+    assert.ok(
+      candidates.indexOf('/opt/homebrew/bin/claude') < candidates.indexOf('/Users/tester/Library/pnpm/claude'),
+      'homebrew candidates should stay ahead of npm-family shims',
+    );
+    assert.ok(
+      candidates.indexOf('/Users/tester/.claude/local/claude') < candidates.indexOf('/Users/tester/Library/pnpm/claude'),
+      'native compatibility wrappers should stay ahead of pnpm shims',
+    );
+  });
+
+  it('win32 search dirs include pnpm and claude local compatibility paths', () => {
+    const home = 'C:\\Users\\tester';
+    const dirs = getExtraPathDirsFor('win32', home, {
+      APPDATA: 'C:\\Users\\tester\\AppData\\Roaming',
+      LOCALAPPDATA: 'C:\\Users\\tester\\AppData\\Local',
+      PNPM_HOME: 'C:\\Users\\tester\\AppData\\Local\\pnpm',
+    } as unknown as NodeJS.ProcessEnv);
+
+    assert.ok(dirs.includes('C:\\Users\\tester\\AppData\\Local\\pnpm'));
+    assert.ok(dirs.includes('C:\\Users\\tester\\.claude\\local'));
+  });
+
+  it('win32 candidates include pnpm cmd wrappers', () => {
+    const home = 'C:\\Users\\tester';
+    const candidates = getClaudeCandidatePathsFor('win32', home, {
+      APPDATA: 'C:\\Users\\tester\\AppData\\Roaming',
+      LOCALAPPDATA: 'C:\\Users\\tester\\AppData\\Local',
+      PNPM_HOME: 'C:\\Users\\tester\\AppData\\Local\\pnpm',
+    } as unknown as NodeJS.ProcessEnv);
+
+    assert.ok(candidates.includes('C:\\Users\\tester\\AppData\\Local\\pnpm\\claude.cmd'));
+    assert.ok(candidates.includes('C:\\Users\\tester\\.claude\\local\\claude.cmd'));
+    assert.ok(
+      candidates.indexOf('C:\\Users\\tester\\.claude\\local\\claude.cmd') <
+        candidates.indexOf('C:\\Users\\tester\\AppData\\Local\\pnpm\\claude.cmd'),
+      'native compatibility wrappers should stay ahead of pnpm shims on Windows',
+    );
+  });
+});
diff --git a/src/lib/platform.ts b/src/lib/platform.ts
index 416d52c4..d674946b 100644
--- a/src/lib/platform.ts
+++ b/src/lib/platform.ts
@@ -62,31 +62,92 @@ export function getRuntimeArchitectureInfo(): RuntimeArchitectureInfo {
  * Extra PATH directories to search for Claude CLI and other tools.
  */
 export function getExtraPathDirs(): string[] {
-  const home = os.homedir();
-  if (isWindows) {
-    const appData = process.env.APPDATA || path.join(home, 'AppData', 'Roaming');
-    const localAppData = process.env.LOCALAPPDATA || path.join(home, 'AppData', 'Local');
-    return [
-      path.join(home, '.local', 'bin'),
-      path.join(home, '.claude', 'bin'),
-      path.join(home, '.bun', 'bin'),
-      path.join(appData, 'npm'),
-      path.join(localAppData, 'npm'),
-      path.join(home, '.npm-global', 'bin'),
-      path.join(home, '.nvm', 'current', 'bin'),
-    ];
+  return getExtraPathDirsFor(process.platform, os.homedir(), process.env);
+}
+
+function getPathApiForPlatform(platform: NodeJS.Platform): typeof path.posix | typeof path.win32 {
+  return platform === 'win32' ? path.win32 : path.posix;
+}
+
+export function getClaudeSearchDirsFor(
+  platform: NodeJS.Platform,
+  home: string,
+  env: NodeJS.ProcessEnv = process.env,
+): string[] {
+  const pathApi = getPathApiForPlatform(platform);
+  const pnpmHome = env.PNPM_HOME;
+  const voltaHome = env.VOLTA_HOME ? pathApi.join(env.VOLTA_HOME, 'bin') : undefined;
+
+  const dirs = platform === 'win32'
+    ? [
+        pathApi.join(home, '.local', 'bin'),
+        pathApi.join(home, '.claude', 'bin'),
+        pathApi.join(home, '.claude', 'local'),
+        pathApi.join(home, '.bun', 'bin'),
+        pathApi.join(home, '.yarn', 'bin'),
+        pathApi.join(home, '.config', 'yarn', 'global', 'node_modules', '.bin'),
+        voltaHome,
+        pathApi.join(home, '.fnm', 'current', 'bin'),
+        pathApi.join(home, '.nvm', 'current', 'bin'),
+        pathApi.join(home, '.asdf', 'shims'),
+        pathApi.join(env.APPDATA || pathApi.join(home, 'AppData', 'Roaming'), 'npm'),
+        pathApi.join(env.LOCALAPPDATA || pathApi.join(home, 'AppData', 'Local'), 'npm'),
+        pathApi.join(env.APPDATA || pathApi.join(home, 'AppData', 'Roaming'), 'pnpm'),
+        pathApi.join(env.LOCALAPPDATA || pathApi.join(home, 'AppData', 'Local'), 'pnpm'),
+        pnpmHome,
+        pathApi.join(home, '.npm-global', 'bin'),
+      ]
+    : [
+        pathApi.join(home, '.local', 'bin'),
+        pathApi.join(home, '.claude', 'bin'),
+        pathApi.join(home, '.claude', 'local'),
+        pathApi.join(home, '.bun', 'bin'),
+        '/opt/homebrew/bin',
+        '/usr/local/bin',
+        '/usr/bin',
+        '/bin',
+        pathApi.join(home, '.npm-global', 'bin'),
+        pathApi.join(home, '.yarn', 'bin'),
+        pathApi.join(home, '.config', 'yarn', 'global', 'node_modules', '.bin'),
+        pathApi.join(home, '.volta', 'bin'),
+        pathApi.join(home, '.fnm', 'current', 'bin'),
+        pathApi.join(home, '.nvm', 'current', 'bin'),
+        pathApi.join(home, '.asdf', 'shims'),
+        pnpmHome,
+        pathApi.join(home, '.local', 'share', 'pnpm'),
+        ...(platform === 'darwin' ? [pathApi.join(home, 'Library', 'pnpm')] : []),
+      ];
+
+  return [...new Set(dirs.filter((dir): dir is string => !!dir))];
+}
+
+export function getExtraPathDirsFor(
+  platform: NodeJS.Platform,
+  home: string,
+  env: NodeJS.ProcessEnv = process.env,
+): string[] {
+  return getClaudeSearchDirsFor(platform, home, env);
+}
+
+export function getClaudeCandidatePathsFor(
+  platform: NodeJS.Platform,
+  home: string,
+  env: NodeJS.ProcessEnv = process.env,
+): string[] {
+  const pathApi = getPathApiForPlatform(platform);
+  const dirs = getClaudeSearchDirsFor(platform, home, env);
+  if (platform === 'win32') {
+    const exts = ['.cmd', '.exe', '.bat', ''];
+    const candidates: string[] = [];
+    for (const dir of dirs) {
+      for (const ext of exts) {
+        candidates.push(pathApi.join(dir, 'claude' + ext));
+      }
+    }
+    return [...new Set(candidates)];
   }
-  return [
-    path.join(home, '.local', 'bin'),
-    path.join(home, '.claude', 'bin'),
-    path.join(home, '.bun', 'bin'),
-    '/usr/local/bin',
-    '/opt/homebrew/bin',
-    '/usr/bin',
-    '/bin',
-    path.join(home, '.npm-global', 'bin'),
-    path.join(home, '.nvm', 'current', 'bin'),
-  ];
+
+  return [...new Set(dirs.map(dir => pathApi.join(dir, 'claude')))];
 }
 
 /**
@@ -100,10 +161,22 @@ export function classifyClaudePath(binPath: string): ClaudeInstallType {
   // Native installer: ~/.local/bin/claude or ~/.claude/bin/claude
   if (normalized.includes('/.local/bin/')) return 'native';
   if (normalized.includes('/.claude/bin/')) return 'native';
+  if (normalized.includes('/.claude/local/')) return 'native';
   // Bun: ~/.bun/bin/claude
   if (normalized.includes('/.bun/bin/') || normalized.includes('/.bun/install/')) return 'bun';
   // Homebrew: /opt/homebrew/bin or /usr/local/Cellar or homebrew in path
   if (normalized.includes('/homebrew/') || normalized.includes('/Cellar/')) return 'homebrew';
+  // npm-family: npm/pnpm/yarn/Node manager shims that resolve to the same package channel
+  if (normalized.includes('/Library/pnpm/')
+    || normalized.includes('/.local/share/pnpm/')
+    || normalized.includes('/.config/yarn/')
+    || normalized.includes('/.yarn/bin/')
+    || normalized.includes('/.volta/bin/')
+    || normalized.includes('/.fnm/current/bin/')
+    || normalized.includes('/.asdf/shims/')
+    || normalized.includes('/.nvm/current/bin/')) {
+    return 'npm';
+  }
   // npm: npm-global, .npm, AppData/npm
   if (normalized.includes('/npm') || normalized.includes('npm-global')) return 'npm';
   if (normalized === '/usr/local/bin/claude') {
@@ -121,6 +194,8 @@ export function classifyClaudePath(binPath: string): ClaudeInstallType {
     const localAppData = (process.env.LOCALAPPDATA || '').replace(/\\/g, '/');
     if (appData && normalized.startsWith(appData + '/npm')) return 'npm';
     if (localAppData && normalized.startsWith(localAppData + '/npm')) return 'npm';
+    if (appData && normalized.startsWith(appData + '/pnpm')) return 'npm';
+    if (localAppData && normalized.startsWith(localAppData + '/pnpm')) return 'npm';
     if (normalized.includes(home.replace(/\\/g, '/') + '/.local/bin')) return 'native';
   }
   return 'unknown';
@@ -131,37 +206,7 @@ export function classifyClaudePath(binPath: string): ClaudeInstallType {
  * Priority: native install > homebrew > npm (deprecated).
  */
 export function getClaudeCandidatePaths(): string[] {
-  const home = os.homedir();
-  if (isWindows) {
-    const appData = process.env.APPDATA || path.join(home, 'AppData', 'Roaming');
-    const localAppData = process.env.LOCALAPPDATA || path.join(home, 'AppData', 'Local');
-    const exts = ['.cmd', '.exe', '.bat', ''];
-    // Native first, then bun, then npm paths
-    const baseDirs = [
-      path.join(home, '.local', 'bin'),
-      path.join(home, '.claude', 'bin'),
-      path.join(home, '.bun', 'bin'),
-      path.join(appData, 'npm'),
-      path.join(localAppData, 'npm'),
-      path.join(home, '.npm-global', 'bin'),
-    ];
-    const candidates: string[] = [];
-    for (const dir of baseDirs) {
-      for (const ext of exts) {
-        candidates.push(path.join(dir, 'claude' + ext));
-      }
-    }
-    return candidates;
-  }
-  // macOS/Linux: native first, then bun, then homebrew, then npm paths
-  return [
-    path.join(home, '.local', 'bin', 'claude'),      // native installer
-    path.join(home, '.claude', 'bin', 'claude'),      // native alt
-    path.join(home, '.bun', 'bin', 'claude'),         // bun global
-    '/opt/homebrew/bin/claude',                        // homebrew (Apple Silicon)
-    '/usr/local/bin/claude',                           // homebrew (Intel) or npm global
-    path.join(home, '.npm-global', 'bin', 'claude'),  // npm custom prefix
-  ];
+  return getClaudeCandidatePathsFor(process.platform, os.homedir(), process.env);
 }
 
 export interface ClaudeInstallInfo {