antigravity-implement

name	antigravity-implement
description	Delegate implementation of an approved plan to Antigravity CLI (agy) via `agy --headless --approve all`, then summarize the resulting diff. Use as an alternative to codex-implement when Codex is unavailable or at its limit.

antigravity-implement

Hand implementation work to Antigravity CLI while Claude Code stays the orchestrator/evaluator. See docs/antigravity.md for the full workflow.

When to use

• A plan is ready and Codex is unavailable or near its limit.
• You want a different model to implement to get a fresh perspective.
• $ARGUMENTS contains the task or plan file path.

Prerequisites

Antigravity CLI must be installed and authenticated:

# Install
curl -fsSL https://antigravity.google/cli/install.sh | bash

# Authenticate (first time — opens browser for Google auth)
agy

Steps

1. Check that Antigravity CLI is available:

   command -v agy
   

   If not found, stop and report: "Antigravity CLI (agy) is not installed on this machine. Install with: curl -fsSL https://antigravity.google/cli/install.sh | bash. Alternatively run /codex-implement if Codex is available."
2. Identify the task source, in this order: $ARGUMENTS → the approved plan file → the newest .tmp/plan*.md. If none exists, ask the user what to implement.
3. Ensure .tmp/progress.md is current (run the handoff skill first if stale).
4. Run Antigravity non-interactively with --headless --approve all (auto-accepts file edits) using run_in_background:

   agy --headless --approve all -p "Implement the plan in <plan-file>. Follow the standards in .claude/AGENTS.md. Keep changes focused; do not commit.
   
   Plan:
   $(cat <plan-file>)"
   

   Antigravity writes files directly. Monitor terminal output for progress. Note: even in headless mode, Antigravity applies OS-level sandbox protection (macOS: sandbox-exec).
5. When Antigravity finishes, run git diff (and git status) and evaluate the result:
   • Correctness: does it match the plan?
   • Standards: does it follow .claude/AGENTS.md?
   • Quality: any obvious issues?
6. Accept the changes, request fixes, or revert (git checkout -- .) if the output is unacceptable.
7. Update .tmp/progress.md (Done/Next/Open). Flag anything that needs follow-up review with /antigravity-review or /code-review.

Notes

• --headless --approve all auto-accepts all tool calls (file writes, shell commands). Confirm the plan is sound before using this flag.
• Antigravity does not have a built-in --json progress stream like Codex's codex exec --json. Use run_in_background and check terminal output when it completes.
• Antigravity edits files itself; do not also edit them from Claude in parallel.
• If Codex is available and the task is complex, prefer /codex-implement — Codex has a more mature autonomous implementation workflow in this setup.
• herdrによる監督レーン自動化(codex-implementのherdr連携を参照)はAntigravityには未対応。herdrの公式エージェント検出一覧にagyは含まれず、agent_status検出の精度が未検証のため、当面は本skillを従来どおり手動運用のまま据え置く。