From 31746e389b3c7164820734793b5fa66b914c1d37 Mon Sep 17 00:00:00 2001 From: robertjamesprior <83608739+robertjamesprior@users.noreply.github.com> Date: Sun, 20 Sep 2026 07:50:47 +0000 Subject: [PATCH 1/2] Add Google Antigravity MCP client page Antigravity has no setup page, so users have to work out the config shape themselves. It uses serverUrl rather than url, and its OAuth flow can leave initialize unauthenticated, so document the API-key header as the fallback. Co-Authored-By: Claude Opus 5 --- docs.json | 1 + reference/mcp-server/clients/antigravity.mdx | 53 ++++++++++++++++++++ 2 files changed, 54 insertions(+) create mode 100644 reference/mcp-server/clients/antigravity.mdx diff --git a/docs.json b/docs.json index 7eca5601..3acf12c5 100644 --- a/docs.json +++ b/docs.json @@ -446,6 +446,7 @@ "pages": [ "reference/mcp-server/clients/claude", "reference/mcp-server/clients/cursor", + "reference/mcp-server/clients/antigravity", "reference/mcp-server/clients/opencode", "reference/mcp-server/clients/fx", "reference/mcp-server/clients/goose", diff --git a/reference/mcp-server/clients/antigravity.mdx b/reference/mcp-server/clients/antigravity.mdx new file mode 100644 index 00000000..0ef41c6b --- /dev/null +++ b/reference/mcp-server/clients/antigravity.mdx @@ -0,0 +1,53 @@ +--- +title: "Google Antigravity" +description: "Connect Google Antigravity to the Kernel MCP server" +--- + + +Antigravity can complete the OAuth flow and still send `initialize` without the bearer token attached, which comes back as `401 Unauthorized` ([antigravity-cli#25](https://github.com/google-antigravity/antigravity-cli/issues/25)). + +If you hit that, [connect with an API key](#connect-with-an-api-key-workaround) instead of OAuth. + + +There's no Kernel CLI target for Antigravity yet, so add the server by hand. + +## Configure manually + +Open the agent side panel, click the ellipsis (**…**) menu, and select **MCP Servers**, then **Manage MCP Servers → View raw config**. Add Kernel to the `mcpServers` map in `mcp_config.json` — `~/.gemini/config/mcp_config.json` globally, or `.agents/mcp_config.json` for a single workspace: + +```json +{ + "mcpServers": { + "kernel": { + "serverUrl": "https://mcp.onkernel.com/mcp" + } + } +} +``` + +Antigravity uses `serverUrl` for remote servers; `url` and `httpUrl` are ignored. Reload the window to pick up the change. + +## Connect + +Press **⌘/Ctrl ,** to open agent settings, go to the **Customizations** tab, and click **Authenticate** next to **kernel**. + +Authorize access in the browser window that opens, then copy the authorization code, paste it back into the settings panel, and click **Submit**. Antigravity stores the tokens in `~/.gemini/antigravity/mcp_oauth_tokens.json` and refreshes them for you. + +## Connect with an API key (workaround) + +Get a project-scoped Kernel API key from the [Kernel Dashboard](https://dashboard.onkernel.com/api-keys) and pass it as a header instead of authenticating: + +```json +{ + "mcpServers": { + "kernel": { + "serverUrl": "https://mcp.onkernel.com/mcp", + "headers": { + "Authorization": "Bearer YOUR_KERNEL_API_KEY" + } + } + } +} +``` + +Leave the **Authenticate** button alone when using this — Antigravity sends the header on every request, including `initialize`. From 23f3c1ecccc4737baf084be6ff275139bf375032 Mon Sep 17 00:00:00 2001 From: robertjamesprior <83608739+robertjamesprior@users.noreply.github.com> Date: Sun, 20 Sep 2026 08:20:56 +0000 Subject: [PATCH 2/2] Document the antigravity CLI install target Co-Authored-By: Claude Opus 5 --- reference/cli/mcp.mdx | 2 ++ reference/mcp-server/clients/antigravity.mdx | 12 +++++++++--- 2 files changed, 11 insertions(+), 3 deletions(-) diff --git a/reference/cli/mcp.mdx b/reference/cli/mcp.mdx index ba5240cb..a7268f25 100644 --- a/reference/cli/mcp.mdx +++ b/reference/cli/mcp.mdx @@ -15,6 +15,7 @@ Install Kernel MCP server configuration for a supported AI development tool. Thi - `cursor` - Cursor editor - `claude` - Claude Desktop app - `claude-code` - Claude Code CLI +- `antigravity` - Google Antigravity - `windsurf` - Windsurf editor - `vscode` - Visual Studio Code - `goose` - Goose AI @@ -51,6 +52,7 @@ The `mcp install` command: The command automatically configures the appropriate transport and settings for each tool: - **Cursor, Claude Code, VS Code, fx**: Uses HTTP transport (`https://mcp.onkernel.com/mcp`) +- **Antigravity**: Uses HTTP transport, keyed off `serverUrl` rather than `url` - **Claude Desktop, Windsurf, Goose, Zed**: Uses stdio transport via `mcp-remote` ### Next Steps diff --git a/reference/mcp-server/clients/antigravity.mdx b/reference/mcp-server/clients/antigravity.mdx index 0ef41c6b..5bf0a941 100644 --- a/reference/mcp-server/clients/antigravity.mdx +++ b/reference/mcp-server/clients/antigravity.mdx @@ -9,11 +9,17 @@ Antigravity can complete the OAuth flow and still send `initialize` without the If you hit that, [connect with an API key](#connect-with-an-api-key-workaround) instead of OAuth. -There's no Kernel CLI target for Antigravity yet, so add the server by hand. +## Install with the Kernel CLI + +Run the following command: + +```bash +kernel mcp install --target antigravity +``` ## Configure manually -Open the agent side panel, click the ellipsis (**…**) menu, and select **MCP Servers**, then **Manage MCP Servers → View raw config**. Add Kernel to the `mcpServers` map in `mcp_config.json` — `~/.gemini/config/mcp_config.json` globally, or `.agents/mcp_config.json` for a single workspace: +Alternatively, open the agent side panel, click the ellipsis (**…**) menu, and select **MCP Servers**, then **Manage MCP Servers → View raw config**. Add Kernel to the `mcpServers` map in `mcp_config.json` — `~/.gemini/config/mcp_config.json` globally, or `.agents/mcp_config.json` for a single workspace: ```json { @@ -35,7 +41,7 @@ Authorize access in the browser window that opens, then copy the authorization c ## Connect with an API key (workaround) -Get a project-scoped Kernel API key from the [Kernel Dashboard](https://dashboard.onkernel.com/api-keys) and pass it as a header instead of authenticating: +Get a project-scoped Kernel API key from the [Kernel Dashboard](https://dashboard.onkernel.com/api-keys) and pass it as a header instead of authenticating. `kernel mcp install --target antigravity` always writes the OAuth config, so add the `headers` block by hand: ```json {