feat: Add support for Antigravity AI agent

.gitignore

@@ -22,6 +22,7 @@ bin/gstack-global-discover*
 .openclaw/
 .hermes/
 .gbrain/
+.gemini/
 .gbrain-source
 .context/
 extension/.auth.json

README.md

@@ -121,6 +121,7 @@ Or target a specific agent with `./setup --host <name>`:
 | Kiro | `--host kiro` | `~/.kiro/skills/gstack-*/` |
 | Hermes | `--host hermes` | `~/.hermes/skills/gstack-*/` |
 | GBrain (mod) | `--host gbrain` | `~/.gbrain/skills/gstack-*/` |
+| Antigravity | `--host antigravity` | `~/.gemini/config/skills/gstack-*/` |
 
 **Want to add support for another agent?** See [docs/ADDING_A_HOST.md](docs/ADDING_A_HOST.md).
 It's one TypeScript config file, zero code changes.

hosts/antigravity.ts

@@ -0,0 +1,48 @@
+import type { HostConfig } from '../scripts/host-config';
+
+const antigravity: HostConfig = {
+  name: 'antigravity',
+  displayName: 'Antigravity',
+  cliCommand: 'antigravity',
+  cliAliases: [],
+
+  globalRoot: '.gemini/config/skills/gstack',
+  localSkillRoot: '.agents/skills/gstack',
+  hostSubdir: '.gemini',
+  usesEnvVars: true,
+
+  frontmatter: {
+    mode: 'allowlist',
+    keepFields: ['name', 'description'],
+    descriptionLimit: null,
+  },
+
+  generation: {
+    generateMetadata: false,
+    skipSkills: ['codex'],
+  },
+
+  pathRewrites: [
+    { from: '~/.claude/skills/gstack', to: '~/.gemini/config/skills/gstack' },
+    { from: '.claude/skills/gstack', to: '.agents/skills/gstack' },
+    { from: '.claude/skills', to: '.agents/skills' },
+  ],
+
+  suppressedResolvers: ['GBRAIN_CONTEXT_LOAD', 'GBRAIN_SAVE_RESULTS'],
+
+  runtimeRoot: {
+    globalSymlinks: ['bin', 'browse/dist', 'browse/bin', 'design/dist', 'gstack-upgrade', 'ETHOS.md', 'review/specialists', 'qa/templates', 'qa/references', 'plan-devex-review/dx-hall-of-fame.md'],
+    globalFiles: {
+      'review': ['checklist.md', 'design-checklist.md', 'greptile-triage.md', 'TODOS-format.md'],
+    },
+  },
+
+  install: {
+    prefixable: false,
+    linkingStrategy: 'symlink-generated',
+  },
+
+  learningsMode: 'basic',
+};
+
+export default antigravity;

hosts/index.ts

@@ -16,9 +16,10 @@ import cursor from './cursor';
 import openclaw from './openclaw';
 import hermes from './hermes';
 import gbrain from './gbrain';
+import antigravity from './antigravity';
 
 /** All registered host configs. Add new hosts here. */
-export const ALL_HOST_CONFIGS: HostConfig[] = [claude, codex, factory, kiro, opencode, slate, cursor, openclaw, hermes, gbrain];
+export const ALL_HOST_CONFIGS: HostConfig[] = [claude, codex, factory, kiro, opencode, slate, cursor, openclaw, hermes, gbrain, antigravity];
 
 /** Map from host name to config. */
 export const HOST_CONFIG_MAP: Record<string, HostConfig> = Object.fromEntries(
@@ -65,4 +66,4 @@ export function getExternalHosts(): HostConfig[] {
 }
 
 // Re-export individual configs for direct import
-export { claude, codex, factory, kiro, opencode, slate, cursor, openclaw, hermes, gbrain };
+export { claude, codex, factory, kiro, opencode, slate, cursor, openclaw, hermes, gbrain, antigravity };

test/host-config.test.ts

@@ -30,8 +30,8 @@ const ROOT = path.resolve(import.meta.dir, '..');
 // ─── hosts/index.ts ─────────────────────────────────────────
 
 describe('hosts/index.ts', () => {
-  test('ALL_HOST_CONFIGS has 10 hosts', () => {
-    expect(ALL_HOST_CONFIGS.length).toBe(10);
+  test('ALL_HOST_CONFIGS has 11 hosts', () => {
+    expect(ALL_HOST_CONFIGS.length).toBe(11);
   });
 
   test('ALL_HOST_NAMES matches config names', () => {