Antigravity

Google's Antigravity editor. Like Windsurf, it uses serverUrl rather than url — and unlike most of the others, it will reject url outright rather than half-working.

Before you start#

You need: Antigravity installed.

You will know it worked when: The MCP panel lists gradworkbench and does not report a configuration error.

Your workspace address is your app's address with /api/mcp on the end. The block on Settings → Research Access has yours already filled in, with a copy button — use that rather than typing it.

Where the file goes#

• ~/.gemini/config/mcp_config.json — everywhere. Use this one.
• .agents/mcp_config.json in a project folder — that project only.

You can also get there from the interface: click the … at the top of the agent side panel, choose MCP Servers, then Manage MCP Servers to open the raw configuration.

Sign in — the short way#

1. Put this in ~/.gemini/config/mcp_config.json:

{
  "mcpServers": {
    "gradworkbench": {
      "serverUrl": "https://gradworkbench.vercel.app/api/mcp"
    }
  }
}

2. Save it and reload the MCP servers from the panel.

3. Antigravity opens a browser to sign in. Approve the connection. It registers itself with your workspace automatically — you do not need to create anything on the GradWorkbench side first.

Use a key instead#

1. In Settings → Research Access, issue a key with Read your workspace and Submit research ticked. Copy it — it is shown once.

2. Add a headers block:

{
  "mcpServers": {
    "gradworkbench": {
      "serverUrl": "https://gradworkbench.vercel.app/api/mcp",
      "headers": { "Authorization": "Bearer sk_your_key_here" }
    }
  }
}

3. Save and reload.

Connect the second one, so research gets checked#

Whatever submits a finding is refused when it tries to confirm that same finding. Add a second entry, with a second key that has Read your workspace and Check research ticked — and not Submit research:

{
  "mcpServers": {
    "gradworkbench": {
      "serverUrl": "https://gradworkbench.vercel.app/api/mcp",
      "headers": { "Authorization": "Bearer sk_your_first_key" }
    },
    "gradworkbench-verify": {
      "serverUrl": "https://gradworkbench.vercel.app/api/mcp",
      "headers": { "Authorization": "Bearer sk_your_second_key" }
    }
  }
}

Try it#

In the agent panel:

What's in my GradWorkbench workspace? Just summarise it — don't research anything.

If it comes back with your universities and professor counts, you are connected. Go to what to actually say.

When it doesn't work#

The entry is rejected — you used url or httpUrl. Antigravity supports neither for remote servers; it must be serverUrl.

Nothing appears — check the path. It is ~/.gemini/config/mcp_config.json, with the config folder in the middle, not ~/.gemini/mcp_config.json.

A project config is being ignored — .agents/mcp_config.json applies only when that folder is the open workspace. The home-folder file is the one that always applies.

← Back to Connecting your assistant