@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