fix(setup): register root gstack slash alias

test/gen-skill-docs.test.ts

@@ -2273,6 +2273,20 @@ describe('setup script validation', () => {
     expect(fnBody).toContain('rm -f "$target"');
   });
 
+  test('setup links root gstack skill through a thin Claude wrapper alias', () => {
+    const fnStart = setupContent.indexOf('link_claude_root_skill_alias()');
+    const fnEnd = setupContent.indexOf('# ─── Helper: remove old unprefixed Claude skill entries', fnStart);
+    const fnBody = setupContent.slice(fnStart, fnEnd);
+    expect(fnBody).toContain('_gstack-command');
+    expect(fnBody).toContain('_link_or_copy "$gstack_dir/SKILL.md" "$target/SKILL.md"');
+
+    const claudeSection = setupContent.slice(
+      setupContent.indexOf('# 4. Install for Claude'),
+      setupContent.indexOf('# 5. Install for Codex')
+    );
+    expect(claudeSection).toContain('link_claude_root_skill_alias "$SOURCE_GSTACK_DIR" "$INSTALL_SKILLS_DIR"');
+  });
+
   test('setup supports --host auto|claude|codex|kiro|opencode', () => {
     expect(setupContent).toContain('--host');
     expect(setupContent).toContain('claude|codex|kiro|factory|opencode|auto');

test/relink.test.ts

@@ -187,6 +187,37 @@ describe('gstack-relink (#578)', () => {
     expect(fs.lstatSync(path.join(skillsDir, 'qa', 'SKILL.md')).isSymbolicLink()).toBe(true);
   });
 
+  test('creates a thin root alias wrapper for the /gstack slash command', () => {
+    setupMockInstall(['qa']);
+    fs.writeFileSync(
+      path.join(installDir, 'SKILL.md'),
+      '---\nname: gstack\ndescription: root\n---\n# gstack',
+    );
+
+    run(`${path.join(installDir, 'bin', 'gstack-config')} set skill_prefix false`, {
+      GSTACK_INSTALL_DIR: installDir,
+      GSTACK_SKILLS_DIR: skillsDir,
+    });
+    run(`${path.join(installDir, 'bin', 'gstack-relink')}`, {
+      GSTACK_INSTALL_DIR: installDir,
+      GSTACK_SKILLS_DIR: skillsDir,
+    });
+
+    const aliasDir = path.join(skillsDir, '_gstack-command');
+    const aliasSkill = path.join(aliasDir, 'SKILL.md');
+    expect(fs.lstatSync(aliasDir).isDirectory()).toBe(true);
+    expect(fs.lstatSync(aliasDir).isSymbolicLink()).toBe(false);
+    expect(fs.lstatSync(aliasSkill).isSymbolicLink()).toBe(true);
+    expect(fs.readlinkSync(aliasSkill)).toBe(path.join(installDir, 'SKILL.md'));
+    expect(fs.readFileSync(aliasSkill, 'utf-8')).toContain('name: gstack');
+
+    run(`${path.join(installDir, 'bin', 'gstack-config')} set skill_prefix true`, {
+      GSTACK_INSTALL_DIR: installDir,
+      GSTACK_SKILLS_DIR: skillsDir,
+    });
+    expect(fs.existsSync(aliasSkill)).toBe(true);
+  });
+
   // FIRST INSTALL: --no-prefix must create ONLY flat names, zero gstack-* pollution
   test('first install --no-prefix: only flat names exist, zero gstack-* entries', () => {
     setupMockInstall(['qa', 'ship', 'review', 'plan-ceo-review', 'gstack-upgrade']);