Google Antigravity

Install

nah hook antigravity install

Restart Antigravity and inspect the nah entry with /hooks. The managed global hook is shared by Antigravity CLI (agy) and the Antigravity desktop application. Remove only nah's entry with:

nah hook antigravity uninstall

The installer atomically updates ~/.gemini/config/hooks.json, preserves other named hooks, and refuses to replace a non-nah entry named nah.

Behavior

The global PreToolUse hook matches commands, reads, writes, single and multi-edits, directory listings, filename searches, and content searches. Blocks return Antigravity's native deny response with nah-branded feedback. For calls nah does not block, it returns Antigravity's native ask decision.

Antigravity does not provide a delegate decision for PreToolUse: its hook API requires allow, deny, ask, or force_ask. nah uses ask rather than allow because nah only blocks or returns control to the runtime; it must not auto-approve a call. Antigravity's normal approval flow and its Always Allow cache can then approve the request. Tools outside the matcher do not invoke nah and use Antigravity's normal permission flow directly.

Task operations, web and browser tools, MCP tools, permission requests, scheduling, agent coordination, media generation, and future tools are outside the matcher and remain runtime-owned. Malformed known inputs and evaluation failures return ask; evaluation failures also write fixed feedback to the hook diagnostic channel.

Boundaries

ask respects Antigravity's Always Allow cache; force_ask does not. always-proceed changes Antigravity's native permission prompt but does not document disabling hooks.

Hook loading, the hook's enabled setting, /hooks, workspace trust, and runtime failure or timeout behavior remain Antigravity-owned. Google does not document whether hook errors and timeouts fail open or closed. Workspace hooks and plugins under .agents/ or _agents/, and global plugins under either documented Antigravity plugin directory, can add interception paths. nah does not protect those additional workspace or plugin paths and cannot inspect work performed directly inside a trusted plugin. Human ! terminal commands, headless/print-mode hook coverage that Google has not documented, remote environments without the installed nah binary, and tool effects outside the intercepted call path remain outside nah. Gemini CLI is a separate legacy and enterprise runtime and is not covered by this integration.

While active, this adapter blocks visible lifecycle commands, explicit native removal or disable commands naming nah, and mutations to the shared hooks.json that keeps nah loaded. Other runtime and plugin configuration remains user-owned. The agent is told not to retry; an operator can use nah nap from another terminal.

This integration is best effort: runtime APIs and hook behavior can change. After upgrades, verify the latest official upstream documentation linked below, inspect the loaded hook, and test it before relying on nah. See Google's hook reference, CLI overview, plugin reference, and Antigravity CLI changelog.