Agent Architecture

Antigravity CLI

Antigravity CLI is the terminal surface of Google's Antigravity platform. Current public evidence indicates a migration path from Gemini CLI toward Antigravity, with CLI, desktop app, SDK, plugins, hooks, skills, and subagents positioned as a unified multi-agent backend.

Source reviewed #17Checked 2026-07-06

Setup guide Source

Run type

CLI

Adapter

json-stdio

Source

Closed / product homepage

Stars

Frontier

Archive Context

This page is one host entry inside the full architecture archive and keeps multi-surface products visible instead of collapsing them into a single run type.

42 host archive

Host page

antigravity-cli

Run cohort

CLI: 30

Archive route

/agents

Host Surface Perspectives

The host is the primary architecture boundary. Each runnable surface below separates what the host owns from what agent-connector can safely install for Antigravity CLI.

1 surface entry

CLI

cli

Host entry: A terminal command owns the process, current working directory, stdin/stdout, shell environment, and project file discovery.
Host owns: The CLI host owns agent loop timing, approval prompts, tool execution, session files, and how hook or MCP subprocesses are launched.
Connector role: agent-connector can only write the host's documented CLI config, prompt, memory, hook, MCP, or package files and point them at the home binary. Current wired connector surfaces: MCP server, Hooks, Commands, Skills, Memory, Statusline handler.
Implementation consequence: A CLI surface is byte-addressable and smoke-testable from a temporary HOME, but terminal UI behavior still belongs to the host process. No visible host-native gap is currently tracked for this surface.

Verified Architecture

Source-checked on 2026-07-06. These notes are intentionally separate from the generated surface matrix below.

Sequence #17

Source pass

Current source review findings are kept as the first architecture section so readers can separate external evidence from the generated local coverage model.

Google Antigravity's official site presents a next-generation agent platform with download-first product onboarding and multi-surface use cases.
The CLI adapter row should stay separate from the desktop IDE row because agent-connector installs a command-line integration target here.
Official page evidence supports an agent-platform classification, but hook, MCP, and memory details still need local adapter evidence before expansion.

Runtime boundary

The adapter target is the Antigravity terminal CLI, but the current product story is a unified backend shared with a desktop app and SDK. The page must separate the CLI install target from the larger Antigravity platform.

Public reporting says Gemini CLI users were directed toward Antigravity CLI in 2026.
The CLI is described as part of a multi-agent platform rather than a standalone terminal experiment.
The official Antigravity site is source-light, so internal claims should remain cautious.

MCP registration

MCP should be documented only where the Antigravity CLI or local adapter exposes a concrete registration contract. Migration from Gemini CLI does not automatically transfer Gemini's settings shape or MCP behavior.

A unified backend may change how tools are registered across desktop and CLI.
The connector archive should avoid reusing Gemini CLI file paths for Antigravity.

Hook bridge

Current public reporting says hooks were among the Gemini CLI features ported to Antigravity, but event details need official Antigravity docs or adapter tests before they become hard claims.

The page can mark hooks as a reported/platform capability with evidence boundaries.
Exact event names and payloads should not be copied from Gemini CLI by analogy.

Content surfaces

Antigravity CLI content surfaces should be separated into skills, subagents, plugins, extensions, SDK workflows, and CLI prompts. These are likely platform-level artifacts rather than simple terminal prompt files.

Agent Skills and Subagents are reported as supported migration features.
Extensions becoming Antigravity plugins suggests a marketplace or plugin packaging layer.

Marketplace and host-only affordances

The host-only affordance is Google's unified multi-agent platform direction: CLI, desktop, SDK, plugins, background tasks, and migration from Gemini CLI. The row should be marked source-light until official docs expose stable local contracts.

The Antigravity CLI and desktop app should stay separate rows in the coverage page.
Migration status is important for users who expect Gemini CLI parity.

Host-specific shape

Antigravity CLI is the terminal surface for Google's Antigravity family with MCP, json-stdio hooks, commands, skills, memory, and statusline wired; subagents are plugin-bundle-only rather than a user file surface.

Form factor: CLI.
Native surfaces: MCP server, Hooks, Commands, Skills, Memory, Statusline handler.
Wired surfaces: MCP server, Hooks, Commands, Skills, Memory, Statusline handler.
Visible gaps: none.

Hooks

Hooks enter through a host-launched command that exchanges event JSON over stdio.

MCP

The adapter writes this host's native MCP registration dialect, including its root key, scope, transport fields, and environment syntax.

Memory

Managed memory text is written into the rules or memory file this host actually reads, with ownership markers for reversible uninstall.

Marketplace and affordances

A marketplace or plugin-driver path is wired, so install/update/uninstall can be driven rather than only emitted as files.

Runtime handlers: Statusline handler.
User-visible affordances: Users see managed commands + skills + statusline + memory surfaces after install; runtime-only surfaces stay behind the host boundary..

Known Limits

Official Antigravity docs were source-light during this pass.
Do not import Gemini CLI paths or event schemas without Antigravity-specific evidence.
Reported migration features need fresh source checks before release claims expand.

Evidence checked

Google Antigravity Antigravity 2.0 migration report Google Antigravity official site

Architecture Diagram

Host-specific flow for the CLI surface.

json-stdio

1
Entry point: CLI
Terminal agent process reads user/project config and invokes the connector home binary for runtime callbacks.
2
Connector package
defineConnector package declares server, hooks, content, memory, and actions.
3
Adapter module: antigravity-cli
json-stdio renderer at src/adapters/antigravity-cli/index.ts.
4
Native host artifacts
Adapter writes MCP config + hook config + content files + memory/rules + statusline + marketplace bundle through this host's native file, package, or marketplace surface.
5
Runtime boundary
host launches JSON-stdio hook command
6
User-visible surface
Users see managed commands + skills + statusline + memory surfaces after install; runtime-only surfaces stay behind the host boundary.
7
Coverage ceiling
6/6 native surfaces wired. No visible host-native gap in the current coverage matrix.

Component Diagram

Static parts of the Antigravity CLI integration and which side owns each one.

Antigravity CLI host
CLI surface owns the model loop, UI shell, config discovery, and native lifecycle for this integration.
agent-connector package
Normalizes connector declarations into MCP, hook, memory, content, and action payloads before delegating to a host adapter.
antigravity-cli adapter
Implements the json-stdio translation layer in src/adapters/antigravity-cli/index.ts.
Native artifacts
Adapter writes MCP config + hook config + content files + memory/rules + statusline + marketplace bundle through this host's native file, package, or marketplace surface.
Runtime bridge
host launches JSON-stdio hook command
User-visible surface
Users see managed commands + skills + statusline + memory surfaces after install; runtime-only surfaces stay behind the host boundary.

Runtime Sequence Flow

Message order from install to runtime for the CLI surface.

1 · User / project
Choose host adapter
Install or update starts against Antigravity CLI; the selected surface is CLI.
2 · agent-connector
Resolve connector declaration
The package reads connector metadata and routes it to the antigravity-cli adapter instead of exposing a generic host contract.
3 · antigravity-cli adapter
Render host-native shape
Adapter writes MCP config + hook config + content files + memory/rules + statusline + marketplace bundle through this host's native file, package, or marketplace surface.
4 · Antigravity CLI
Host loads artifacts
host launches JSON-stdio hook command
5 · Agent runtime
Run through host boundary
Users see managed commands + skills + statusline + memory surfaces after install; runtime-only surfaces stay behind the host boundary.
6 · Coverage matrix
Expose remaining ceiling
6/6 native surfaces wired. No visible host-native gap in the current coverage matrix.

Architecture Archive

The same five study axes are rendered for every host: runtime shape, hooks, MCP, memory, and host-only affordances.

Host-specific shape

Form factor: CLI.
Native surfaces: MCP server, Hooks, Commands, Skills, Memory, Statusline handler.
Wired surfaces: MCP server, Hooks, Commands, Skills, Memory, Statusline handler.
Visible gaps: none.

Hooks

Hooks enter through a host-launched command that exchanges event JSON over stdio.

MCP

The adapter writes this host's native MCP registration dialect, including its root key, scope, transport fields, and environment syntax.

Memory

Managed memory text is written into the rules or memory file this host actually reads, with ownership markers for reversible uninstall.

Marketplace and affordances

A marketplace or plugin-driver path is wired, so install/update/uninstall can be driven rather than only emitted as files.

Runtime handlers: Statusline handler.
User-visible affordances: Users see managed commands + skills + statusline + memory surfaces after install; runtime-only surfaces stay behind the host boundary..

Special Feature Inventory

Host-specific capabilities separated from the generic surface matrix: lifecycle hooks, MCP registration, memory/rules, marketplace delivery, and UI or content affordances owned by the host.

Lifecycle hooks

Wired

Hooks enter through a host-launched command that exchanges event JSON over stdio.

MCP registration

Wired

The adapter writes this host's native MCP registration dialect, including its root key, scope, transport fields, and environment syntax.

Memory and rules

Wired

Managed memory text is written into the rules or memory file this host actually reads, with ownership markers for reversible uninstall.

Marketplace delivery

Driver wired

A marketplace or plugin-driver path is wired, so install/update/uninstall can be driven rather than only emitted as files.

Host-only affordances

3/3 wired

Wired host affordances: Commands, Skills, Statusline handler. Host-native gaps: none. Not confirmed: Subagents, Action affordances.

Source Review Notes

Latest source pass for host-specific architecture details. This is separate from generated adapter coverage and local drift guards.

Checked 2026-07-06Open review source

Google Antigravity official site

Google Antigravity's official site presents a next-generation agent platform with download-first product onboarding and multi-surface use cases.
The CLI adapter row should stay separate from the desktop IDE row because agent-connector installs a command-line integration target here.
Official page evidence supports an agent-platform classification, but hook, MCP, and memory details still need local adapter evidence before expansion.

Evidence Map

Each host page ties public source evidence to the local adapter and drift guards that keep the rendered archive aligned with code.

Product source

Official product homepage or public tracker used when no open product repository is confirmed.

external

Open source

Local adapter implementation

Defines the install/uninstall behavior, native config rendering, capability flags, and any runtime parse/format bridge for this host.

local

src/adapters/antigravity-cli/index.ts

Platform metadata and host-native matrix

Records the form factor, public source target, ranking source, native host surfaces, and current agent-connector coverage cells.

local

site/src/platform-data.ts

Architecture drift guard

Asserts that every registered host has a page, diagram, host-specific brief, source link, form-factor band, and adapter-aligned surface data.

local

tests/docs/platform-drift.test.ts

Marketplace driver registry

Shows this host has a drivable package/plugin install path beyond direct native-file writes.

local

src/core/marketplace-drivers/registry.ts

Runtime Shape

Hooks are dispatched through a host-launched command. The adapter parses host JSON, calls the connector handler, and formats the reply back to the host contract.

MCP registration: Wired through this adapter
Hook bridge: Wired

Connector Surfaces

Static content

MCP server, Hooks, Commands, Skills, Memory

Runtime handlers

Statusline handler

Surface Matrix

Wired means agent-connector installs it now. Host native marks support we know about but have not wired yet.

SurfaceStatus

MCP server

Static content

agent-connector installs this surface today.

Wired

Hooks

Static content

agent-connector installs this surface today.

Wired

Commands

Static content

agent-connector installs this surface today.

Wired

Skills

Static content

agent-connector installs this surface today.

Wired

Subagents

Static content

No confirmed host-native surface.

N/A

Memory

Static content

agent-connector installs this surface today.

Wired

Statusline handler

Runtime handler

agent-connector installs this surface today.

Wired

Action affordances

Runtime handler

No confirmed host-native surface.

N/A