Antigravity

Google Antigravity reads MCP servers from a single config file that the desktop app and the CLI both share, so you set Engram up once and get it in both. Antigravity handles OAuth automatically for servers that support dynamic client registration, which Engram does. For protocol background, see MCP.

Note

Antigravity CLI is the successor to Gemini CLI, which Google retired on 2026-06-18. Config lives under ~/.gemini/ for that reason. Coming from Gemini CLI’s settings.json, note that the remote-server key changed from httpUrl to serverUrl. For the Gemini app, see Gemini.

Caution

Antigravity uses serverUrl for remote MCP servers. The url and httpUrl keys that most other clients accept are not supported, and using them fails with Error: serverUrl or command must be specified.

Prerequisites

Before you start, confirm:

• You have an Engram account at app.engram.page.
• At least one vault is synced. Open the Obsidian plugin or the web app and confirm notes have synced within the last day.
• You can sign in via browser. The MCP auth flow opens a browser window.

Endpoint

https://mcp.engram.page

Setup

1. Open the config. All three Antigravity surfaces read the same files:

Scope	Path
Global (desktop app + CLI)	~/.gemini/config/mcp_config.json
Workspace	.agents/mcp_config.json in your project or git root

Reach the global file from whichever surface you use:

• Antigravity 2.0: Settings (bottom left) → Customizations → Installed MCP Servers.
• Antigravity IDE: click … at the top of the agent side panel → MCP Servers → Manage MCP Servers → View raw config.
• Antigravity CLI: type /mcp in the prompt panel to open the interactive MCP Manager, or edit the file directly.

Some older IDE builds open ~/.gemini/antigravity/mcp_config.json instead. Whichever path View raw config opens is the one that build reads.

2. Add the engram entry.

{
  "mcpServers": {
    "engram": {
      "serverUrl": "https://mcp.engram.page"
    }
  }
}

3. Reload. In the CLI, reload from the /mcp overlay. In the desktop app, hit the refresh button in the MCP servers list, or restart Antigravity if the entry doesn’t appear.

First-run auth

Engram advertises OAuth 2.1 with dynamic client registration, so Antigravity needs no client ID or secret. Unlike most clients, it doesn’t complete the flow purely in the browser; you copy a code back:

1. Open Agent Settings with Cmd+, (Mac) or Ctrl+, (Windows/Linux).
2. Go to the Customizations tab and click Authenticate next to engram.
3. Sign in to Engram in the browser, approve the connection, and copy the authorization code it shows you.
4. Paste the code back into the settings panel and click Submit.

The server reconnects on its own. Antigravity stores the token at ~/.gemini/antigravity/mcp_oauth_tokens.json, refreshes it when it expires, and discards it if it goes invalid. The grant is the full mcp scope. Granular per-action scopes are on the roadmap.

Tool permissions

Antigravity runs any MCP tool you haven’t explicitly allowed in Ask mode, prompting you before each call. Once you trust the connection, pre-approve Engram in your permissions policy:

mcp(engram/search)   allow one tool
mcp(engram/*)        allow every Engram tool

Pre-approving reads you use constantly is reasonable. Leave writes on Ask until you trust the flow, because the mcp grant covers write and delete.

Tell Antigravity how to use it

Antigravity rules are Markdown files, capped at 12,000 characters each. Add the snippet below to ~/.gemini/GEMINI.md for user-wide rules, or to a file under .agents/rules/ in a workspace. You can also create them from Customizations → Rules → + Global or + Workspace.

Engram holds my personal notes — treat it as your long-term memory of me. Search it when a question depends on context I might have shared before. Before saving or updating a note, ask first.

Set the rule’s activation to Always On so it applies without an @ mention.

Try it

Once connected, ask the agent:

• Search my vault for notes about the engineering interview process and summarize the top three.
• Find anything I wrote about embeddings in the last month.

Antigravity calls Engram’s search (or get_note, write_note, etc.) tool, pulls back results, and answers in-context. If the tool fires, you’re set.

API key instead of OAuth

The Authenticate button lives in the desktop settings panel, so a CLI-only, headless, or shared-vault setup should use an Engram API key in a headers block instead:

{
  "mcpServers": {
    "engram": {
      "serverUrl": "https://mcp.engram.page",
      "headers": { "Authorization": "Bearer YOUR_ENGRAM_API_KEY" }
    }
  }
}

Generate a key at app.engram.page/settings/api-keys and treat it like any service credential: keep it out of source control and rotate it when teammates rotate off. See MCP Config → API Key Authentication.

Troubleshooting (Antigravity specific)

• Error: serverUrl or command must be specified. You used url or httpUrl. Rename the key to serverUrl.
• Config edits do nothing. You edited a file that build doesn’t read. Use View raw config to open the one it actually loads, and check whether a workspace .agents/mcp_config.json is overriding your global entry.
• The status ring never turns green. Some builds leave the indicator stale even when the connection is live. Ask the agent to call an Engram tool by name; if it returns results, the server is fine. Check the connection logs in the /mcp overlay (CLI) if it doesn’t.
• No Authenticate button. The OAuth panel is part of the desktop Agent Settings. On a CLI-only or headless host, use the API key block above.
• Every tool call stops for approval. That’s Ask mode. Add mcp(engram/*) to your permissions policy.

For cross-client failures, see Troubleshooting.

Revocation

To disconnect Antigravity from Engram:

1. In Antigravity, find the connector or MCP server entry and remove it.
2. In Engram, open your account → API Keys & Sessions and revoke the matching session.
3. The OAuth token is invalidated server-side. Antigravity will need to re-authenticate to reconnect.

To drop it client-side, delete the engram entry from mcp_config.json and reload. Removing the stored token as well means deleting the engram entry from ~/.gemini/antigravity/mcp_oauth_tokens.json.

Next steps

MCPProtocol overview.

ScopesWhat the grant covers.

All integrationsPick a different client.