@bacnh85/pi-agy

Google Antigravity CLI (agy) bridge for the Pi coding agent.

Offload bulk implementation, scaffolding, repetitive refactors, and exhaustive test generation to Gemini, Claude, or GPT-OSS through agy, while Pi retains the conductor role for judgement and verification.

Install

pi install npm:@bacnh85/pi-agy

Prerequisites

Install the Antigravity CLI (a Go binary, not pipx):

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

Windows PowerShell:

irm https://antigravity.google/cli/install.ps1 | iex

Authenticate (one-time in your terminal):

agy

Verify the CLI works:

agy --version
agy models

Tool

agy_execute

| Param | Type | Default | Description | |-------|------|---------|-------------| | prompt | string | required | Task instruction for agy | | model | model alias below | flash-medium | Antigravity model; takes precedence over tier | | tier | flash / flash-lo / pro | — | Legacy Gemini tier compatibility | | mode | accept-edits / plan / sandbox | accept-edits | agy execution mode | | dir | string | cwd | Working directory | | digest | boolean | mode-based | Compact output; defaults on for plan/sandbox and off for accept-edits | | timeout_ms | number | 300000 | Timeout in milliseconds |

Models

Aliases map to agy's canonical machine names (run agy models to list them):

| Alias | agy machine name | Typical use | |-------|------------------|-------------| | flash-low | gemini-3.6-flash-low | Trivial, few-step, high-volume work | | flash-medium | gemini-3.6-flash-medium | Default coding, exploration, and tests | | flash-high | gemini-3.6-flash-high | Difficult agentic work | | pro-low | gemini-3.1-pro-low | Advanced reasoning | | pro-high | gemini-3.1-pro-high | Hardest Gemini reasoning | | sonnet | claude-sonnet-4-6 | Normal Claude coding and review | | opus | claude-opus-4-6-thinking | Hardest architecture and root-cause review | | gpt-oss | gpt-oss-120b-medium | Alternative open model |

Resolution order is explicit model, then explicit legacy tier, then flash-medium. Legacy mappings remain flash → flash-high, flash-lo → flash-low, and pro → pro-high. Run agy models if Antigravity changes its display names or plan availability.

Quota-aware routing

| Work | Produce | Cross-review when consequential | |------|---------|---------------------------------| | Routine bulk work | flash-medium (Gemini quota group) | sonnet with mode=plan | | Claude-group implementation | sonnet (Claude quota group) | flash-medium with mode=plan | | Hard reasoning | Escalate to pro-high or opus only after the cheaper model is insufficient | Opposite family |

Batch related work, prefer digest=true for non-write calls, and avoid parallel calls inside one shared-quota group. Do not spend both groups on trivial tasks. Pi should review the diff and run verification after every accept-edits call.

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

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

How pi-agy shapes the handoff

Pi delegates to agy as a producer, not an autonomous agent. Each call is framed so the result is verifiable and parseable — this is where pi-agy adds value over running agy bare:

• Mode-aware flags. plan is read-only. accept-edits and sandbox both write, so pi-agy passes --dangerously-skip-permissions for them (headless -p mode auto-denies writes without it). plan/sandbox additionally get --output-format json.
• Phase-aware prompt framing. plan prompts are prefixed to explore only; sandbox notes isolation; accept-edits gets a verify-loop line.
• Verify-loop injection. In accept-edits, if the project's package.json has a test script, pi-agy appends After editing, run \npm test` and fix failures until it passes.` — implementing Google's own Best Practices ("provide a local verification mechanism… run the local test command").
• Structured output. plan/sandbox return JSON; pi-agy extracts the .response field so Pi receives the answer, not the raw envelope (with a safe fallback to raw text on schema drift).

Safety

• Pre-flight checks verify agy is installed and the CLI can reach its backend (agy --version + agy models).
• agy always runs with detached stdin (stdio: ['ignore', 'pipe', 'pipe']) to prevent hanging.
• --dangerously-skip-permissions is used only for accept-edits/sandbox (the modes that write), scoped to the --add-dir workspace; plan never receives it.
• Output is truncated to 8000 characters to protect Pi's context window.
• Always review the git diff after accept-edits mode.

Development

npm test

Changelog

See CHANGELOG.md for release history.

License

MIT