Connecting Claude, Copilot, Cursor, and Open WebUI

Once Bifrost’s MCP server is enabled (see Server Setup), any MCP-compliant client can connect. This page walks through Claude Desktop, GitHub Copilot, Cursor, and Open WebUI.

The general flow is the same for all of them:

1. Tell the client the MCP server URL (https://your-instance/mcp).
2. The client kicks off OAuth: it registers via /register, redirects you to Bifrost’s login, and exchanges the code for a token.
3. Tools matching your roles appear in the client.

Claude Desktop

1. Open Claude Desktop’s settings file:

   • macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
   • Windows: %APPDATA%\Claude\claude_desktop_config.json

2. Add a mcpServers entry pointing at Bifrost. Claude Desktop uses the streamable HTTP transport for hosted MCP servers:

   {
     "mcpServers": {
       "bifrost": {
         "url": "https://your-instance.com/mcp"
       }
     }
   }

3. Restart Claude Desktop. The first time you mention a Bifrost tool, Claude opens the OAuth flow in your browser.

4. Sign in to Bifrost. Claude receives the access token and your tools appear in the tool tray.

Tip

If Claude Desktop doesn’t trigger the OAuth popup, check Settings → Developer → MCP Servers for connection errors. The most common issue is a stale client_id cache after re-enabling MCP — restart Claude to re-register.

GitHub Copilot

1. In VS Code, open Settings (JSON) and add an mcp.servers entry:

   {
     "mcp.servers": {
       "bifrost": {
         "url": "https://your-instance.com/mcp"
       }
     }
   }

2. Reload VS Code. Open the Copilot Chat panel and type @bifrost — Copilot prompts you to authorize.

3. Click Sign in and complete the Bifrost login. Tool calls now flow through Copilot Chat.

Cursor

1. Open Cursor’s settings (Cmd/Ctrl + ,) and search for MCP.

2. Add a server entry:

   {
     "mcpServers": {
       "bifrost": {
         "url": "https://your-instance.com/mcp"
       }
     }
   }

3. Restart Cursor. The first tool call triggers the OAuth login in your browser.

Open WebUI

1. In Open WebUI, go to Admin Settings → External Tools → MCP.

2. Click Add MCP Server and enter the Bifrost URL (https://your-instance.com/mcp). Open WebUI auto-discovers the OAuth endpoints.

3. Click Authorize, complete the Bifrost login, and approve the tool list. Tools now appear under the model’s tool tray.

What tools become available

The exact tool list depends on:

• The Allowed / Blocked Tools lists in Settings → MCP.
• Your user’s roles (the roles claim on the JWT).
• Which agents have your roles in their access list — only those agents’ workflow tools and system_tools appear.

To see exactly what’s exposed, query GET /api/mcp/tools with your user token, or run the connected client’s “list tools” command.

Troubleshooting

Symptom	Likely cause
OAuth flow opens but never returns	Client redirect URI doesn’t match. Re-register the client (delete and re-add the server).
401 on every request	Bifrost MCP toggle is off. Re-enable in Settings → MCP.
Empty tool list, but connection succeeds	User has no roles matching any agent. Assign the user a role and reconnect.
Cross-origin error in browser-based client	Verify the discovery endpoints serve Access-Control-Allow-Origin: *.

Next steps

• Configuring the MCP server
• Publishing agents as MCP tool providers