Antigravity

Use OpenKnowledge with Google Antigravity — the agentic IDE and the agy terminal agent — over MCP.

Antigravity is Google's agentic development platform: an IDE and the agy terminal agent (the successor to the Gemini CLI). Both connect to MCP servers. Once OpenKnowledge is registered as one, Antigravity can read, search, and write your knowledge base through OK's tools — with full attribution, link-awareness, conflict-awareness, and a live browser preview. Inside an OK project, work markdown through those tools rather than native file access, so every edit stays attributed and previewable.

Install

There are two ways to connect Antigravity, depending on how you run OpenKnowledge:

macOS desktop app. The first time you open a project, a consent dialog detects Antigravity and configures it for you. To re-trigger the dialog, choose File → Set up OpenKnowledge integrations….
Web app / terminal (Linux, Windows, Intel Mac — see the web app guide). Run ok init in your project: it registers the OpenKnowledge MCP server with Antigravity and the other editors it detects. Every ok start repairs the entry if it has drifted (it never adds one you removed).

After ok init writes the config, restart Antigravity (or reload MCP servers from the agent panel) so it picks up the entry. The IDE and the agy CLI share one config file, so a single ok init wires up both.

ok init writes the OpenKnowledge server into ~/.gemini/config/mcp_config.json under mcpServers, using the same resilient launcher every other editor gets — it finds ok whether you installed the desktop app or the npm CLI, so there's no PATH to configure.

Antigravity has one shared, user-global MCP config — ~/.gemini/config/mcp_config.json, read by the IDE, the app, and agy alike (the .gemini directory is inherited from the Gemini CLI lineage, not ~/.antigravity). There is no per-project MCP config; per project you can only choose which globally-registered servers an agent may use. So OpenKnowledge registers once, globally, the same way it does for Claude Desktop. Each OK tool call takes a cwd argument to target a specific knowledge base, so one registration serves every project you open.

Verify

Open a project with Antigravity — the IDE or an agy session in the project directory — and ask:

Antigravity should call the OpenKnowledge exec tool and respond with some of your documents.

If the agent doesn't see the tool, reload the MCP servers (the agent panel's Manage MCP Servers view, or restart agy) and check that OpenKnowledge is listed and enabled. The first tool call can take a moment on a fresh machine — the launcher may be installing the OpenKnowledge CLI via npx.

Use the `agy` CLI

agy is Antigravity's terminal agent. Start it in a knowledge base and pass an opening prompt as the positional argument:

cd /path/to/your/knowledge-base
agy "Summarize the open questions across this project's specs."

The session stays open for follow-ups. From the OpenKnowledge desktop app, the "Open in Antigravity" action launches agy in the docked terminal, pre-filled with a prompt scoped to the doc, folder, or project you're on. The row appears only when agy is detected on your PATH (the installer drops it at ~/.local/bin/agy).

Initialize a knowledge base

ok init turns a folder into a knowledge base (and, on the same run, registers the MCP server above):

cd /path/to/your/knowledge-base && ok init

ok init resolves upward into an existing project. Run inside a subdirectory of an existing OK project, ok init finds the parent project and refreshes that one — it does not create a nested project, and it writes no markdown in the subdirectory. To create a genuinely separate knowledge base, run ok init in a folder that sits outside any existing .ok project tree.

Preview

Write and edit responses include a route-only preview path like /#/notes/mcp-round-trip — a route id, not a full URL. Call preview_url for the openable browser address, and don't screenshot the preview to confirm an edit (the tool response is the confirmation). See MCP reference → Preview links for the full semantics.

Agent contract

The OpenKnowledge skill — the authoritative agent contract for tool use, grounding, and linking — is project-scoped, written for Claude, Cursor, Codex, and OpenCode. Antigravity reads skills only from its user-global ~/.gemini/skills hub, with no project skill directory to receive it, so for Antigravity the contract is these two reminders:

Markdown is MCP-owned. Inside an OK project, read and write .md / .mdx through OK's tools (exec, search, write, edit, links), not native shell or file tools — native access loses attribution and skips the frontmatter, backlinks, and history OK returns.
Discover before concluding the MCP is missing. Not seeing exec in the initial tool list isn't the escape hatch; reload the MCP servers first.

For the complete tool surface, see the MCP reference.

Troubleshooting

Symptom	Cause	Fix
`ok init` showed Antigravity as `config root missing; skipped`	`~/.gemini/` doesn't exist yet, so Antigravity wasn't detected	Launch Antigravity or run `agy` once (it creates the directory), then re-run `ok init`
`ok init` reported the config was `left unchanged`	OpenKnowledge declined to edit `~/.gemini/config/mcp_config.json` for the reason shown in parentheses	Fix what the reason names (invalid JSON, a duplicated server block), then re-run `ok init`
Antigravity doesn't see the `open-knowledge` tools	MCP servers not reloaded, or the agent's process predates the entry	Reload MCP servers (or restart `agy`), and confirm the server is enabled
"Open in Antigravity" row is missing in the desktop app	`agy` isn't on `PATH`	Install the Antigravity CLI (`~/.local/bin/agy`) and ensure that directory is on your `PATH`
`write` / `edit` -> "Hocuspocus server is not running"	OK server not started	Run `ok start` (or leave the desktop app running) and retry
Preview "doesn't open"	used the route-only `/#/…` path in a browser	Call `preview_url` for the full URL

New to OpenKnowledge itself? Start with the quickstart for ok init and ok start.