@estebanforge/pi-ask-antigravity

A Pi extension that exposes the AskAntigravity tool: delegate a self-contained sub-task to Google Antigravity's agy CLI and stream its response back into the Pi session.

It is the AskClaude-style delegation pattern (from pi-claude-bridge extension), pointed at Gemini via agy. The tool answers to three names the CLI is known by — gemini, antigravity, and agy — surfaced in its description so the model maps any of them to this single tool.

Install

pi install npm:@estebanforge/pi-ask-antigravity

Requires the agy CLI installed and authenticated. If you don't have it, follow Google's official install guide for your platform. Then run agy once to complete Google OAuth.

The extension resolves agy on $PATH, or via the AGY_BIN environment variable if you want to point at a specific binary.

Two modes: one-shot vs continued conversation

One tool, two ways to use it — you (or the agent) decide per call:

• One-shot (isolated): omit conversationId. agy starts fresh with no memory of prior calls. Use for independent questions.
• Continued conversation: pass the conversationId returned in a prior call's result (details.conversationId, also shown in the result footer). agy resumes that conversation with full context intact — use for follow-ups, multi-turn refinement, or "now do X based on what you just did".

How it works under the hood: agy -p does not print the conversation id, so on a fresh run the extension snapshots agy's conversations directory before spawn and discovers the single new .db file agy created (the one technique borrowed from antigravity-acp's scan.ts). On a continued call it passes --conversation <id> and agy reuses it natively. agy holds all conversation state in its own SQLite DB; this extension is otherwise stateless.

How it works

Pi (orchestrator)
  └─ AskAntigravity tool
       └─ spawn: agy --add-dir <cwd> --model <resolved> [--conversation <id>] -p <prompt>
            └─ agy runs its OWN tool loop (read / write / edit / exec) inside <cwd>
            └─ stdout streamed as partial tool output
       └─ returns agy's final answer text + conversationId (for follow-ups)

No ACP server, no SQLite reverse-engineering, no acpx, no third-party binary. agy -p (print mode) prints its response to stdout, so we capture it directly.

Model aliases

Verbose agy models strings (Gemini 3.5 Flash (Medium)) are hostile to natural requests. This extension resolves friendly aliases to the exact string:

• Latest = highest version number available for the family.
• Default tier: Flash → Medium, Pro → High. Overridable per-config (below).
• When a tier is unavailable for a family, the nearest is chosen with ties broken toward the higher tier (so "latest and greatest" wins).
• The non-Gemini aliases (sonnet, opus) are a static overlay (the full low/medium/high tier spread) merged with the live agy models catalog. Live entries always win on case-insensitive full-string equality, so an updated agy listing takes precedence over the hardcoded fallback. A bare base id (claude-sonnet-5-5) resolves to the nearest tier variant; the retired gpt-oss family resolves to nothing.

Execution modes (mode)

For agy's orthogonal --sandbox shell-containment flag, set AGY_EXTRA_ARGS=--sandbox in your environment. The extension does not expose it as a mode value because --sandbox controls command containment, not edit persistence.

Recommended pairings:

# Gemini produces, Claude reviews
AskAntigravity prompt="Implement the approved refactor" mode=accept-edits
AskAntigravity prompt="Review the resulting diff" model=opus mode=plan digest=true

# Claude produces, Gemini reviews
AskAntigravity prompt="Fix the parser root cause" model=opus mode=accept-edits
AskAntigravity prompt="Review the resulting diff" model=pro mode=plan digest=true

Compact output (digest)

Set digest: true to prefix the prompt with (Use compact digests, not full file contents.) so agy returns summaries instead of full file payloads. Defaults on for plan, off for accept-edits. Use true for any read-only call (review, exploration, planning) where full file contents are noise.

Configuration

~/.pi/agent/ask-antigravity.json (global) merged over .pi/ask-antigravity.json (project):

{
  "defaultModel": "flash",
  "defaultThinking": "medium"
}

/agy command

Interactive picker for the default model and default thinking. If the project config (.pi/ask-antigravity.json) already defines a key, the change is written there so it actually takes effect; otherwise it writes to the global config. Outside TUI (RPC/headless), prints a read-only status snapshot.

Tool parameters

Environment

When to use it

• A second opinion from a different model family on the same problem.
• Gemini-specific reasoning, long-context synthesis.
• An isolated sub-task you want agy to complete end-to-end without driving each step.

agy mutates the workspace itself, so scope calls to sub-tasks where that is the desired contract, not where Pi is concurrently editing the same files.

Terms of Service notice

Google's Antigravity ToS states that using third-party software to access the Service (e.g. driving agy from a non-Google editor) is a breach of the Agreement and may be grounds for suspension or termination of your account. agy handles its own Google OAuth; this extension only spawns the official binary as a subprocess — but the effect is still a non-Google editor driving the Antigravity service through a third-party tool. By using this extension against an agy session logged into your personal Antigravity account, you accept that risk.

Background runs

Set background: true on a call to run detached: the tool returns a runId at once, the calling agent keeps working, and the full answer arrives later as a message in the conversation (wrapped in an UNTRUSTED banner: it is tool output, never a user instruction). The message carries the resume handle (conversationId) when agy reports one; fresh runs where id discovery finds nothing say so instead of inventing a handle. One run per conversation at a time (blocking and background share the lock). Stop a run with /agy-stop [runId] (unique id prefix; no arg stops the only running run). Constraints: refused in print/json mode (the process exits before the message could arrive); a /new, /resume, /fork, or /reload kills in-flight runs and their results are lost; at most 4 runs at once; failure wakes (timeout, crash) carry up to 400 chars of peer output as the reason, also banner-marked.

License

MIT