diff --git a/src/main/startup/configure-process.test.ts b/src/main/startup/configure-process.test.ts
index 922da579d7c..88557fbbc8c 100644
--- a/src/main/startup/configure-process.test.ts
+++ b/src/main/startup/configure-process.test.ts
@@ -56,7 +56,7 @@ describe('patchPackagedProcessPath', () => {
     }
   })
 
-  it('prepends agent-CLI install dirs (~/.opencode/bin, ~/.vite-plus/bin) for packaged darwin runs', async () => {
+  it('seeds agent-CLI install dirs (~/.opencode/bin, ~/.vite-plus/bin, ~/.grok/bin) for packaged darwin runs', async () => {
     const { app } = await import('electron')
     const { patchPackagedProcessPath } = await import('./configure-process')
 
@@ -68,9 +68,10 @@ describe('patchPackagedProcessPath', () => {
     patchPackagedProcessPath()
 
     const segments = (process.env.PATH ?? '').split(':')
-    // #829: GUI PATH must discover the documented OpenCode/Pi fallback installs.
+    // #829/#17590: GUI PATH must discover the documented OpenCode/Pi/Grok fallback installs.
     expect(segments).toContain(join('/Users/tester', '.opencode/bin'))
     expect(segments).toContain(join('/Users/tester', '.vite-plus/bin'))
+    expect(segments).toContain(join('/Users/tester', '.grok/bin'))
     expect(segments).toContain(join('/Users/tester', 'bin'))
   })
 
diff --git a/src/main/startup/configure-process.ts b/src/main/startup/configure-process.ts
index 2ffc58fe2c5..6c7611dfb7e 100644
--- a/src/main/startup/configure-process.ts
+++ b/src/main/startup/configure-process.ts
@@ -151,7 +151,8 @@ export function patchPackagedProcessPath(): void {
         join(home, '.nix-profile/bin'),
         // GUI PATH omits agent-specific install directories (#829).
         join(home, '.opencode/bin'),
-        join(home, '.vite-plus/bin')
+        join(home, '.vite-plus/bin'),
+        join(home, '.grok/bin')
       )
     }
   }
diff --git a/src/shared/agent-cli-install-dir-fallback.test.ts b/src/shared/agent-cli-install-dir-fallback.test.ts
index ee9adb65279..4145e9c0811 100644
--- a/src/shared/agent-cli-install-dir-fallback.test.ts
+++ b/src/shared/agent-cli-install-dir-fallback.test.ts
@@ -134,7 +134,8 @@ describe('agent CLI install-dir fallback', () => {
       '/nix/var/nix/profiles/default/bin',
       join(home, '.nix-profile', 'bin'),
       join(home, '.opencode', 'bin'),
-      join(home, '.vite-plus', 'bin')
+      join(home, '.vite-plus', 'bin'),
+      join(home, '.grok', 'bin')
     ]
     stage(...dirs.map((dir) => join(dir, 'opencode')))
     for (const expected of dirs) {
@@ -193,7 +194,8 @@ describe('agent CLI install-dir fallback', () => {
         '/nix/var/nix/profiles/default/bin',
         join(home, '.nix-profile', 'bin'),
         join(home, '.opencode', 'bin'),
-        join(home, '.vite-plus', 'bin')
+        join(home, '.vite-plus', 'bin'),
+        join(home, '.grok', 'bin')
       ]) {
         expect(seeded).not.toContain(directory)
       }
@@ -208,12 +210,14 @@ describe('agent CLI install-dir fallback', () => {
         join('/usr/local/bin', 'codex'),
         join(MOCK_HOME, '.opencode', 'bin', 'opencode'),
         // Pi defaults to ~/.vite-plus/bin and is probed on every runtime (#829).
-        join(MOCK_HOME, '.vite-plus', 'bin', 'pi')
-      )
-      // All three come from the fallback: the stubbed PATH holds no system dir.
-      expect(detectCommandsInInstallDirs(['codex', 'opencode', 'pi', 'cursor-agent'])).toEqual(
-        new Set(['codex', 'opencode', 'pi'])
+        join(MOCK_HOME, '.vite-plus', 'bin', 'pi'),
+        // Grok's installer defaults to ~/.grok/bin (#17590).
+        join(MOCK_HOME, '.grok', 'bin', 'grok')
       )
+      // All come from the fallback: the stubbed PATH holds no system dir.
+      expect(
+        detectCommandsInInstallDirs(['codex', 'opencode', 'pi', 'grok', 'cursor-agent'])
+      ).toEqual(new Set(['codex', 'opencode', 'pi', 'grok']))
     }
   )
 
@@ -239,7 +243,8 @@ describe('agent CLI install-dir fallback', () => {
         login,
         join(home, '.nvm', 'versions', 'node', 'v24.0.0', 'bin'),
         join(home, '.opencode', 'bin'),
-        join(home, '.vite-plus', 'bin')
+        join(home, '.vite-plus', 'bin'),
+        join(home, '.grok', 'bin')
       ]
       const command = 'orca-fallback-fixture'
       try {
diff --git a/src/shared/posix-version-manager-bin-dirs.ts b/src/shared/posix-version-manager-bin-dirs.ts
index c4606a3dbd5..6d898e53146 100644
--- a/src/shared/posix-version-manager-bin-dirs.ts
+++ b/src/shared/posix-version-manager-bin-dirs.ts
@@ -17,9 +17,10 @@ const POSIX_VERSION_MANAGER_BIN_DIRS = [
   '"/home/linuxbrew/.linuxbrew/bin"',
   '"/nix/var/nix/profiles/default/bin"',
   '"$HOME/.nix-profile/bin"',
-  // Why both: the opencode and Pi installers' own defaults, which no version manager owns (#829).
+  // Installer-owned defaults no version manager covers: opencode, Pi (#829), Grok (#17590).
   '"$HOME/.opencode/bin"',
-  '"$HOME/.vite-plus/bin"'
+  '"$HOME/.vite-plus/bin"',
+  '"$HOME/.grok/bin"'
 ].join(' ')
 
 /** Append behind login PATH so stale fallback nvm installs cannot shadow the user’s selected binary. */
diff --git a/src/shared/system-cli-install-dirs.ts b/src/shared/system-cli-install-dirs.ts
index 8718dedf79e..8d188eb016d 100644
--- a/src/shared/system-cli-install-dirs.ts
+++ b/src/shared/system-cli-install-dirs.ts
@@ -3,7 +3,7 @@ import { join } from 'node:path'
 /** Lookup-only fallback: prepending system dirs to inherited PATH would reorder the user’s binaries (#18234).
  * Keep system-block order aligned with patchPackagedProcessPath/POSIX_VERSION_MANAGER_BIN_DIRS; cross-block precedence differs
  * for ~/.local/bin, which precedes this fallback but follows seeded system dirs. Do not hoist system paths above version managers.
- * Omit sbin/~/bin and off-darwin /opt/homebrew; Linuxbrew has its own prefix. Include installer-owned .opencode/.vite-plus bins (#829).
+ * Omit sbin/~/bin and off-darwin /opt/homebrew; Linuxbrew has its own prefix. Include installer-owned .opencode/.vite-plus (#829) and .grok (#17590) bins.
  * Exception: a newly discovered CLI with sibling node may prepend that dir only to its child PATH for runtime pairing (#10932). */
 export function getSystemCliInstallDirectories(
   platform: NodeJS.Platform,
@@ -27,7 +27,8 @@ export function getSystemCliInstallDirectories(
     '/nix/var/nix/profiles/default/bin',
     join(homePath, '.nix-profile', 'bin'),
     join(homePath, '.opencode', 'bin'),
-    join(homePath, '.vite-plus', 'bin')
+    join(homePath, '.vite-plus', 'bin'),
+    join(homePath, '.grok', 'bin')
   )
   return directories
 }