feat(agents): add Antigravity CLI (agy) as built-in agent

.gitignore

@@ -25,3 +25,6 @@ docs/
 /.ripgreprc
 /.zprofile
 /.zshrc
+
+# Local runtime state from memory/sidecar processes (not source)
+/data/

README.md

@@ -115,10 +115,19 @@ When you're happy with the result, merge the branch back to main from the sideba
    - **macOS** — `.dmg` (universal)
    - **Linux** — `.AppImage` or `.deb`
 
-2. **Install at least one AI coding CLI:** [Claude Code](https://docs.anthropic.com/en/docs/claude-code), [Codex CLI](https://github.com/openai/codex), [Gemini CLI](https://github.com/google-gemini/gemini-cli), or [Copilot CLI](https://docs.github.com/en/copilot/concepts/agents/about-copilot-cli)
+2. **Install at least one AI coding CLI:** [Claude Code](https://docs.anthropic.com/en/docs/claude-code), [Codex CLI](https://github.com/openai/codex), [Gemini CLI](https://github.com/google-gemini/gemini-cli), [Antigravity CLI](https://antigravity.google/), or [Copilot CLI](https://docs.github.com/en/copilot/concepts/agents/about-copilot-cli)
 
 3. **Open Parallel Code**, point it at a git repo, and start dispatching tasks.
 
+<details>
+<summary><strong>Antigravity CLI: run natively, not in Docker isolation</strong></summary>
+
+Antigravity (`agy`) signs in interactively and caches credentials in your OS keyring (Keychain/libsecret). The keyring cannot be reached from inside a Linux container — it needs a secret-service daemon the agent container doesn't run — and `agy` has no API-key fallback, so **Docker-isolated Antigravity tasks cannot authenticate. Run Antigravity as a native (non-Docker) task.**
+
+The bundled image still ships the `agy` binary, and `~/.gemini/antigravity-cli` (settings/plugins) is shared when "Share agent auth" is enabled, so Docker support is forward-compatible if a file-based or API-key auth path appears later.
+
+</details>
+
 <details>
 <summary><strong>Build from source</strong></summary>
 

docker/Dockerfile

@@ -52,6 +52,14 @@ RUN ln -sf "$(command -v fdfind)" /usr/local/bin/fd 2>/dev/null || true
 # AI agent CLIs — must be present so Docker-mode tasks can execute them
 RUN npm install -g @anthropic-ai/claude-code @openai/codex @google/gemini-cli opencode-ai
 
+# Antigravity CLI (agy) — distributed as a Go binary via the official installer
+# (not on npm). The installer's `--dir` flag drops the binary straight into a
+# system path on PATH, so the non-root `agent` user that runs containers resolves
+# it. A failed fetch makes the build step fail, surfacing the break at image build
+# time rather than at task launch.
+RUN curl -fsSL https://antigravity.google/cli/install.sh | bash -s -- --dir /usr/local/bin \
+    && agy --version
+
 # Default git config so commits work out of the box inside containers
 RUN git config --system init.defaultBranch main \
     && git config --system advice.detachedHead false

electron/ipc/agents.ts

@@ -66,6 +66,17 @@ const DEFAULT_AGENTS: AgentDef[] = [
     // settle before sending, without being so long that the user notices the wait.
     prompt_ready_delay_ms: 1_000,
   },
+  {
+    id: 'antigravity',
+    name: 'Antigravity CLI',
+    command: 'agy',
+    args: [],
+    resume_args: ['-c'],
+    skip_permissions_args: ['--dangerously-skip-permissions'],
+    description: "Google's Antigravity CLI agent (successor to Gemini CLI)",
+    // Antigravity paints a TUI that needs a beat to settle before auto-send.
+    prompt_ready_delay_ms: 1_000,
+  },
 ];
 
 async function isCommandAvailable(command: string): Promise<boolean> {

electron/ipc/pty.test.ts

@@ -352,6 +352,7 @@ describe('spawnAgent docker mode', () => {
       ['gemini', '.gemini'],
       ['opencode', '.config/opencode'],
       ['copilot', '.config/github-copilot'],
+      ['agy', '.gemini/antigravity-cli'],
     ])(
       '%s bind-mounts a user-owned host directory when shareDockerAgentAuth is enabled',
       (command, relDir) => {

electron/ipc/pty.ts

@@ -710,6 +710,7 @@ const AGENT_CONFIG_DIRS: Record<string, string[]> = {
   gemini: ['.gemini'],
   opencode: ['.config/opencode'],
   copilot: ['.config/github-copilot'],
+  agy: ['.gemini/antigravity-cli'],
 };
 
 // Config files (not directories) each agent CLI uses for auth, relative to HOME.

electron/mcp/agent-args.test.ts

@@ -1,6 +1,11 @@
 import { describe, expect, it } from 'vitest';
 
-import { buildCodexMcpConfigOverride, buildMcpLaunchArgs, isCodexCommand } from './agent-args.js';
+import {
+  buildCodexMcpConfigOverride,
+  buildMcpLaunchArgs,
+  isAntigravityCommand,
+  isCodexCommand,
+} from './agent-args.js';
 
 const config = {
   mcpServers: {
@@ -50,4 +55,14 @@ describe('MCP agent launch args', () => {
       '/tmp/config.json',
     ]);
   });
+
+  it('detects antigravity commands by executable name', () => {
+    expect(isAntigravityCommand('agy')).toBe(true);
+    expect(isAntigravityCommand('/home/agent/.local/bin/agy')).toBe(true);
+    expect(isAntigravityCommand('claude')).toBe(false);
+  });
+
+  it('emits no --mcp-config for Antigravity', () => {
+    expect(buildMcpLaunchArgs('agy', '/tmp/config.json', config)).toEqual([]);
+  });
 });

electron/mcp/agent-args.ts

@@ -14,6 +14,10 @@ export function isCodexCommand(command: string): boolean {
   return command.split('/').pop()?.includes('codex') === true;
 }
 
+export function isAntigravityCommand(command: string): boolean {
+  return command.split('/').pop() === 'agy';
+}
+
 function tomlString(value: string): string {
   return JSON.stringify(value);
 }
@@ -41,5 +45,9 @@ export function buildMcpLaunchArgs(
   if (isCodexCommand(command)) {
     return ['--config', buildCodexMcpConfigOverride(config)];
   }
+  // Antigravity (agy) has no `--mcp-config` flag; emit nothing so launch is not broken.
+  if (isAntigravityCommand(command)) {
+    return [];
+  }
   return configPath ? ['--mcp-config', configPath] : [];
 }

openspec/changes/add-antigravity-agent/.openspec.yaml

@@ -0,0 +1,2 @@
+schema: spec-driven
+created: 2026-05-29

openspec/changes/add-antigravity-agent/design.md

@@ -0,0 +1,169 @@
+## Context
+
+parallel-code launches coding-agent CLIs in node-pty terminals, one per git
+worktree. The agent catalog is a static `DEFAULT_AGENTS` array in
+`electron/ipc/agents.ts`; each entry is an `AgentDef` (`{ id, name, command,
+args, resume_args, skip_permissions_args, description, prompt_ready_delay_ms?,
+mcp_config_flag? }`). `AgentDef` is **duplicated** — the canonical copy lives in
+`src/ipc/types.ts` and a structurally identical copy in `electron/ipc/agents.ts`.
+
+At launch the agent is started **interactively** with `args` (the initial prompt
+is typed into the TUI afterward via bracketed paste, not passed as a CLI argument).
+`buildTaskAgentArgs` appends `resume_args` on resume and `skip_permissions_args`
+when the task opts into skip-permissions. Availability is probed with `which
+<command>` (TTL-cached). The renderer's `AgentSelector` renders each agent as a
+text button keyed off `agent.id` with **no per-agent icon or color map**, so a new
+agent needs no front-end asset.
+
+The Electron main process resolves the user's full login+interactive shell PATH
+(`zsh/bash -ilc`, `electron/main.ts:52`), so binaries on `~/.local/bin` are
+discoverable as long as the user's shell profile adds that directory.
+
+For Docker-isolated tasks, `AGENT_CONFIG_DIRS` (`electron/ipc/pty.ts:707`) maps a
+command basename to host config dirs that are bind-mounted into the container when
+"Share agent auth" is enabled. The bundled `docker/Dockerfile` installs the other
+agents via `npm install -g`.
+
+Ground truth for `agy` (verified against the installed binary, v1.0.3 — `agy
+--help`):
+
+- Interactive launch: `agy`
+- Resume most recent conversation: `-c` / `--continue`
+- Skip permissions: `--dangerously-skip-permissions`
+- Sandbox (`nsjail`/`sandbox-exec`) is **opt-in** via `--sandbox`; off by default.
+- Non-interactive print mode: `-p` / `--print` (not used by this app).
+- Config/app-data dir is `~/.gemini/antigravity-cli` (settings.json, mcp_config.json,
+  plugins/, conversations/) — verified against the installed binary; it is **not**
+  `~/.config/antigravity`. Interactive auth is OAuth cached in the OS keyring
+  (Keychain/libsecret); `agy` has **no** API-key environment fallback (the
+  `ANTIGRAVITY_API_KEY` variable is not consumed — confirmed behaviorally).
+
+## Goals / Non-Goals
+
+**Goals:**
+
+- Add `agy` as a built-in default agent with correct launch/resume/skip-permission
+  args, fully working on native (macOS/Linux) tasks.
+- Ship the Docker bits that are additive and forward-compatible (bundle the `agy`
+  binary, mount its config dir), while documenting clearly — in user-facing docs and
+  the PR — that Docker-isolated Antigravity cannot authenticate and must be run
+  natively.
+- Keep Gemini CLI fully intact.
+- Make the integration data-driven — no new IPC, no per-id special casing.
+
+**Non-Goals:**
+
+- Removing or deprecating Gemini CLI (separate future change).
+- Wiring `agy`'s OAuth keyring credentials into Docker containers (not file-mountable).
+- Supporting `agy --sandbox` inside Docker (nested sandbox; left off by default).
+- A custom agent-branding/icon system.
+
+## Decisions
+
+**1. Launch interactively with `command: "agy"`, `args: []`.**
+Matches every other agent: the app types the prompt into the live TUI rather than
+passing `-p`. `-p`/`--print` is one-shot and prints-then-exits, which would defeat
+the interactive session model. Rejected `-i`/`--prompt-interactive` because the app
+already delivers the prompt via terminal input after a readiness delay.
+
+**2. `resume_args: ["-c"]`, `skip_permissions_args: ["--dangerously-skip-permissions"]`.**
+Both verified against the installed binary. `--dangerously-skip-permissions` is
+real (it coincidentally matches Claude's flag); the Gemini `--yolo` flag does **not**
+carry over.
+
+**3. `prompt_ready_delay_ms` set to a modest stability delay (~1000 ms), mirroring
+Copilot.** `agy`'s first interactive run shows onboarding (Google sign-in, theme,
+file-permission prompts); steady-state runs still paint a TUI that needs a beat to
+settle before auto-send. This only tunes the readiness recheck; it does not bypass
+first-run OAuth, which is interactive regardless (same caveat as other agents).
+
+**4. Omit `mcp_config_flag` AND exclude `agy` from the `--mcp-config` paths.** `agy`
+has no `--mcp-config` flag (MCP is configured via plugins/config), so passing it would
+break launch. Two code paths can emit it and both must exclude `agy`:
+
+- `legacyMcpConfigArgs` (`src/lib/agent-args.ts`) injects `--mcp-config <path>` for any
+  non-Codex command when a task carries a legacy `mcpConfigPath` and no `mcpLaunchArgs`
+  — reachable only by older persisted tasks.
+- `buildMcpLaunchArgs` (`electron/mcp/agent-args.ts`, imported by `coordinator.ts`) is
+  the modern per-agent builder used by coordinator/MCP tasks.
+  Excluding `agy` (the same way Codex is excluded via `isCodexCommand`) is the safe
+  default: it guarantees `agy` is never handed an unsupported flag regardless of whether
+  a given task takes the legacy or modern path. Leaving `mcp_config_flag` unset keeps it
+  off the flag-driven path as well.
+
+**5. Mount the config dir; Docker auth is unsupported (native only).** Add
+`agy: ['.gemini/antigravity-cli']` to `AGENT_CONFIG_DIRS` so settings/plugins are
+shared. Auth, however, cannot work in Docker: login credentials live in the host OS
+keyring (Keychain/libsecret), which needs a secret-service daemon the agent container
+does not run, and `agy` has no API-key environment fallback (the `ANTIGRAVITY_API_KEY`
+claim was unverified and is false — behaviorally `agy` still enters OAuth with it set).
+So Antigravity is documented as a native-only agent. The mount + bundled binary are
+kept because they are additive and forward-compatible if a file-based or API-key auth
+path appears.
+
+**6. Install `agy` in the Docker image via the official installer, not npm.** `agy`
+ships as a Go binary from `https://antigravity.google/cli/install.sh`, so the existing
+`npm install -g` line cannot add it. The installer supports `-d|--dir`, so the step
+installs straight to a system PATH dir:
+`RUN curl -fsSL … | bash -s -- --dir /usr/local/bin && agy --version`. Verified the
+script runs non-interactively when piped and `mkdir -p`s its target. The trailing
+`agy --version` makes the build assert the install at image-build time.
+
+## Risks / Trade-offs
+
+- **Docker auth is impossible, not just limited** → `agy` login is keyring-only OAuth,
+  the container has no secret-service daemon, and there is no API-key fallback, so an
+  in-container `agy` cannot authenticate at all. Mitigation: native tasks work fully;
+  docs and PR state plainly that Antigravity is native-only and Docker isolation is
+  unsupported for it. The config-dir mount + bundled binary are kept as additive,
+  forward-compatible scaffolding, not a working auth path.
+- **PATH discovery** → If the user never ran the installer's PATH line, `~/.local/bin`
+  is absent from the resolved shell PATH and `agy` shows "(not installed)". Mitigation:
+  this is the same behavior as any un-PATHed agent; the availability probe degrades
+  gracefully. Document running `agy install`.
+- **`--mcp-config` injected by either MCP path** → `legacyMcpConfigArgs` (old tasks)
+  or `buildMcpLaunchArgs` (coordinator tasks) could hand `agy` an unknown flag and
+  break launch. Mitigation: exclude `agy` from both, the way Codex is excluded via
+  `isCodexCommand` — chosen as the safe default rather than relying on the legacy path
+  being unreachable. **Functional consequence (accepted):** `buildMcpLaunchArgs`
+  returning `[]` for `agy` means Antigravity tasks receive no parallel-code MCP
+  coordinator wiring — no in-`agy` subagent spawning. `agy` configures MCP via
+  plugins/config rather than a CLI flag, so coordinator integration is a separate
+  follow-up if desired; this change intentionally ships without it.
+- **Installer-script drift in Docker builds** → Piping a remote installer into the
+  image is less reproducible and could break builds if the URL/format changes.
+  Mitigation: pin behavior to the documented installer; treat a failed fetch as a
+  build error so it is caught at image-build time, not at task launch.
+- **Duplicate `AgentDef` definitions drift** → The entry and the type live in two
+  files. Mitigation: update both `electron/ipc/agents.ts` and `src/ipc/types.ts` in
+  lockstep; TypeScript strict build catches shape mismatches.
+
+## Migration Plan
+
+Additive and behind agent availability detection — no data migration. `agy` appears
+in the selector only when the binary is on PATH; existing Gemini tasks are untouched.
+Rollback is removing the `DEFAULT_AGENTS` entry (and the Dockerfile/ config-dir
+lines); no persisted state depends on it.
+
+## Resolved Decisions
+
+- **Antigravity is native-only; Docker isolation is unsupported for it.** The earlier
+  `ANTIGRAVITY_API_KEY` Docker auth path was an unverified claim and is false. We keep
+  the additive Docker scaffolding (bundled `agy` binary, mounted
+  `~/.gemini/antigravity-cli` config dir) but document Antigravity as native-only.
+  Decided with the user after the Codex review surfaced the wrong config path and the
+  non-functional env var.
+- **`agy` is excluded from both `--mcp-config` paths** (`legacyMcpConfigArgs` and
+  `buildMcpLaunchArgs`), as the safe default — no dependence on the legacy path being
+  unreachable.
+
+## Open Questions
+
+- In-container PATH is resolved: the installer's `--dir` flag installs `agy` to
+  `/usr/local/bin` (on PATH for the non-root `agent` user); the build-step
+  `agy --version` verifies it. A full `docker build` is the only step needing a Docker
+  daemon.
+- **Untested:** whether `agy` can read a file-based credential it shares with the
+  Gemini CLI (`~/.gemini/gemini-credentials.json` / `google_accounts.json` sit in the
+  parent dir). If it does, that could become a real Docker auth path later. Not claimed
+  or relied on here.

openspec/changes/add-antigravity-agent/proposal.md

@@ -0,0 +1,50 @@
+## Why
+
+Google is transitioning the Gemini CLI to the new **Antigravity CLI** (`agy`). On
+**June 18, 2026** Gemini CLI stops serving Google AI Pro/Ultra and free Code Assist
+users; it remains only on paid/enterprise API keys. Users who pick the "Gemini CLI"
+agent today will increasingly hit a dead end, while `agy` becomes the supported
+Google terminal agent. parallel-code should offer Antigravity CLI as a first-class
+agent so users have a working migration path — without yet removing Gemini CLI,
+which paid/enterprise users still rely on.
+
+## What Changes
+
+- Add **Antigravity CLI** (`agy`) as a built-in default agent alongside Claude Code,
+  Codex, Gemini CLI, OpenCode, and Copilot.
+- Register its launch contract: interactive launch (`agy`), resume (`-c`), and
+  skip-permissions (`--dangerously-skip-permissions`).
+- Add its config directory (`~/.gemini/antigravity-cli`) to the Docker shared-auth
+  mount map for settings/plugins, and document that Antigravity is **native-only**:
+  its login credentials live in the OS keyring (no secret-service daemon in the
+  container) and `agy` has no API-key env fallback, so Docker-isolated Antigravity
+  cannot authenticate.
+- Install `agy` in the bundled Docker agent image (via the official installer script,
+  not npm) so the binary is present and the integration is forward-compatible.
+- Keep Gemini CLI unchanged. **No removal, no breaking change.**
+
+## Capabilities
+
+### New Capabilities
+
+- `agent-cli-registry`: The set of coding-agent CLIs parallel-code can launch, and the
+  per-agent contract (command, launch/resume/skip-permission arguments, availability
+  detection, config-directory auth mounting for Docker isolation) that governs how each
+  agent is started, resumed, and authenticated.
+
+### Modified Capabilities
+
+<!-- None: no existing capability spec governs the agent registry today. -->
+
+## Impact
+
+- **Code:** `electron/ipc/agents.ts` (`DEFAULT_AGENTS`), `src/ipc/types.ts` +
+  `electron/ipc/agents.ts` (`AgentDef` — duplicated, both updated),
+  `electron/ipc/pty.ts` (`AGENT_CONFIG_DIRS`), `docker/Dockerfile` (install `agy`).
+- **No new IPC channels or payload-type changes** — Antigravity reuses the existing
+  data-driven `AgentDef` plumbing; the selector renders it from the agent list with no
+  per-id branding.
+- **Dependencies:** the Docker image gains the `agy` binary fetched from
+  `https://antigravity.google/cli/install.sh`.
+- **Tests:** agent-registry and persistence tests that enumerate agents may need the
+  new entry accounted for.