diff --git a/scripts/claude_version_utils.cjs b/scripts/claude_version_utils.cjs
index 921729e5..087e897c 100644
--- a/scripts/claude_version_utils.cjs
+++ b/scripts/claude_version_utils.cjs
@@ -9,6 +9,7 @@
  *    - macOS/Linux: curl -fsSL https://claude.ai/install.sh | bash
  *    - PowerShell:  irm https://claude.ai/install.ps1 | iex
  *    - Windows CMD: curl -fsSL https://claude.ai/install.cmd | cmd
+ * 4. PATH fallback: bun, pnpm, or any other package manager
  */
 
 const { execSync } = require('child_process');
@@ -249,6 +250,26 @@ function findLatestVersionBinary(versionsDir, binaryName = null) {
     return null;
 }
 
+/**
+ * Find path to Claude Code CLI using system PATH lookup (which/where)
+ * This serves as a fallback for non-standard installations (e.g., bun, pnpm)
+ * @returns {string|null} Path to claude binary, or null if not found
+ */
+function findWhichCliPath() {
+    try {
+        const cmd = process.platform === 'win32' ? 'where claude' : 'which claude';
+        const result = execSync(cmd, { encoding: 'utf8', stdio: ['pipe', 'pipe', 'pipe'] }).trim();
+        // which/where may return multiple lines, take the first
+        const firstPath = result.split('\n')[0].trim();
+        if (firstPath && fs.existsSync(firstPath)) {
+            return resolvePathSafe(firstPath) || firstPath;
+        }
+    } catch (e) {
+        // which/where command failed (claude not in PATH)
+    }
+    return null;
+}
+
 /**
  * Find path to globally installed Claude Code CLI
  * Checks multiple installation methods in order of preference:
@@ -270,6 +291,10 @@ function findGlobalClaudeCliPath() {
     const nativePath = findNativeInstallerCliPath();
     if (nativePath) return { path: nativePath, source: 'native installer' };
 
+    // Fallback: use which/where to find claude in PATH
+    const whichPath = findWhichCliPath();
+    if (whichPath) return { path: whichPath, source: 'PATH' };
+
     return null;
 }