diff --git a/src/lib/programs/error-tracking-upload-source-maps/index.ts b/src/lib/programs/error-tracking-upload-source-maps/index.ts
index 80db004f5..e4fb26f4a 100644
--- a/src/lib/programs/error-tracking-upload-source-maps/index.ts
+++ b/src/lib/programs/error-tracking-upload-source-maps/index.ts
@@ -41,7 +41,7 @@ function ensurePostHogCli(variant: SkillVariant): void {
     analytics.captureException(
       result.errorObject ??
         new Error(`posthog-cli pre-install failed: ${result.error}`),
-      { source: 'source_maps_cli_preinstall', variant },
+      { source: 'source_maps_cli_preinstall', variant, detail: result.detail },
     );
     getUI().log.warn(
       `Could not pre-install posthog-cli (${result.error}). Your release build ` +
diff --git a/src/steps/install-cli-steering/__tests__/install-cli-steering.test.ts b/src/steps/install-cli-steering/__tests__/install-cli-steering.test.ts
index 19a0b9c8f..ee72eb6a3 100644
--- a/src/steps/install-cli-steering/__tests__/install-cli-steering.test.ts
+++ b/src/steps/install-cli-steering/__tests__/install-cli-steering.test.ts
@@ -82,6 +82,80 @@ describe('install-cli-steering', () => {
       expect(result.error).toContain('install failed');
     });
 
+    it('gives every npm failure a stable exception message so they group', () => {
+      spawnSyncMock.mockReturnValue({
+        status: 1,
+        stdout: '',
+        stderr: `npm error path ${os.homedir()}\\AppData\\Roaming\\npm\n`,
+      });
+
+      const result = installOrUpdatePostHogCli();
+      expect(result.errorObject?.message).toBe(
+        'npm install --global @posthog/cli@latest failed',
+      );
+    });
+
+    it('drops personal data from the reported detail', () => {
+      const home = os.homedir();
+      spawnSyncMock.mockReturnValue({
+        status: 1,
+        stdout: '',
+        stderr: [
+          'npm error code E404',
+          'npm error 404 Not Found - GET https://registry.npmjs.org/@posthog/cli',
+          `npm error path ${home}\\AppData\\Roaming\\npm`,
+          `npm error command ${home}\\node.exe install`,
+          `npm error A complete log is in ${home}\\npm-cache\\log`,
+        ].join('\n'),
+      });
+
+      const result = installOrUpdatePostHogCli();
+      expect(result.detail).not.toContain(home);
+      expect(result.detail).not.toContain('npm error path');
+      expect(result.detail).not.toContain('npm error command');
+      // Keeps the diagnosable bits: HTTP status and the failing registry URL.
+      expect(result.detail).toContain('E404');
+      expect(result.detail).toContain('registry.npmjs.org');
+      expect(result.error).not.toContain(home);
+    });
+
+    it('keeps the exit status when npm fails with no output', () => {
+      spawnSyncMock.mockReturnValue({
+        status: 1,
+        signal: null,
+        stdout: '',
+        stderr: '',
+      });
+
+      const result = installOrUpdatePostHogCli();
+      expect(result.success).toBe(false);
+      // Grouping message stays stable...
+      expect(result.errorObject?.message).toBe(
+        'npm install --global @posthog/cli@latest failed',
+      );
+      // ...but the exit status survives in the error and detail so a silent
+      // failure is still distinguishable.
+      expect(result.error).toContain('exited with status 1');
+      expect(result.detail).toContain('exited with status 1');
+    });
+
+    it('keeps the terminating signal when npm is killed with no output', () => {
+      spawnSyncMock.mockReturnValue({
+        status: null,
+        signal: 'SIGKILL',
+        stdout: '',
+        stderr: '',
+      });
+
+      const result = installOrUpdatePostHogCli();
+      expect(result.success).toBe(false);
+      expect(result.errorObject?.message).toBe(
+        'npm install --global @posthog/cli@latest failed',
+      );
+      expect(result.error).toContain('terminated by signal SIGKILL');
+      expect(result.detail).toContain('terminated by signal SIGKILL');
+    });
+
     it('explains when npm itself cannot be run', () => {
       spawnSyncMock.mockReturnValue({
         error: new Error('spawn npm ENOENT'),
diff --git a/src/steps/install-cli-steering/index.ts b/src/steps/install-cli-steering/index.ts
index 45e133219..12d7451e6 100644
--- a/src/steps/install-cli-steering/index.ts
+++ b/src/steps/install-cli-steering/index.ts
@@ -73,6 +73,12 @@ export interface CliInstallResult {
    * false.
    */
   errorObject?: Error;
+  /**
+   * Sanitized npm output for callers to attach as an exception property. Keeps
+   * the HTTP status and CLI version out of the grouping message while the
+   * message itself stays stable. Truncated and free of personal data.
+   */
+  detail?: string;
 }
 
 const spawnOptions = {
@@ -82,6 +88,31 @@ const spawnOptions = {
   shell: process.platform === 'win32',
 };
 
+/** Stable message so npm install failures group into one error-tracking issue. */
+const NPM_INSTALL_FAILED_MESSAGE =
+  'npm install --global @posthog/cli@latest failed';
+
+/** Cap on the sanitized npm output stored as an exception property. */
+const NPM_FAILURE_DETAIL_LIMIT = 1000;
+
+/**
+ * Strip personal data from npm's output before it reaches error tracking. npm
+ * prints `npm error path <dir>` and `npm error command <cmd>` lines that carry
+ * the user's name and home directory, so drop those lines and redact any home
+ * directory that remains.
+ */
+function sanitizeNpmFailure(raw: string): string {
+  const home = os.homedir();
+  const cleaned = raw
+    .split('\n')
+    .filter((line) => {
+      const normalized = line.trim().toLowerCase();
+      return !/^npm (error|err!) (path|command)\b/.test(normalized);
+    })
+    .join('\n');
+  return (home ? cleaned.split(home).join('~') : cleaned).trim();
+}
+
 /**
  * Install or update the PostHog CLI in the user's environment. `npm install
  * --global @posthog/cli@latest` covers both first-time installs and upgrades
@@ -101,16 +132,22 @@ export function installOrUpdatePostHogCli(): CliInstallResult {
     };
   }
   if (result.status !== 0) {
-    const detail = (result.stderr || result.stdout || '').trim();
-    const message =
-      detail ||
-      `npm install --global @posthog/cli@latest exited with status ${
-        result.status ?? 'unknown'
-      }`;
+    const detail = sanitizeNpmFailure(result.stderr || result.stdout || '');
+    // A quieted npm (e.g. `--loglevel=silent` from .npmrc) can exit non-zero
+    // with no output. The exit status or terminating signal is then the only
+    // diagnostic left, so fall back to it instead of a bare constant. Neither
+    // is personal data, and the stable `errorObject` message still groups these
+    // failures into one issue regardless of the fallback text.
+    const exitDetail = result.signal
+      ? `npm install --global @posthog/cli@latest terminated by signal ${result.signal}`
+      : `npm install --global @posthog/cli@latest exited with status ${
+          result.status ?? 'unknown'
+        }`;
     return {
       success: false,
-      error: message,
-      errorObject: new Error(message),
+      error: detail || exitDetail,
+      errorObject: new Error(NPM_INSTALL_FAILED_MESSAGE),
+      detail: detail.slice(0, NPM_FAILURE_DETAIL_LIMIT) || exitDetail,
     };
   }
   return { success: true };