claudeai-mcp-bridge

Disclaimer: This project is not affiliated with, endorsed by, or officially supported by Anthropic. It is an independent, experimental project for educational and research purposes. It uses undocumented internal APIs that may change or break at any time. Using Claude subscription tokens outside official clients may violate Anthropic's Terms of Service. Use at your own risk -- no warranty is provided.

Use your claude.ai connectors (Slack, Atlassian, Gmail, Google Calendar) inside any MCP client -- zero credential setup.

This is a standard MCP server (stdio) that bridges connectors you've already authorized through claude.ai into any MCP-compatible tool. Works with OpenCode, Claude Desktop, Cursor, Cline, Windsurf, and more.

How it works

┌────────────┐  stdio (MCP)  ┌──────────────────┐   HTTPS    ┌──────────────────┐
│ Any MCP    │──────────────>│ This MCP Server  │──────────>│ mcp-proxy.       │
│ Client     │<──────────────│                  │<──────────│ anthropic.com    │
│            │  tools/list   │ Reads Keychain   │           │                  │
│ OpenCode   │  tools/call   │ Discovers servers│           │ Slack, Atlassian │
│ Claude     │               │ Proxies calls    │           │ Gmail, Calendar  │
│ Desktop    │               └──────────────────┘           └──────────────────┘
│ Cursor     │
│ ...        │
└────────────┘

1. Reads your OAuth token from macOS Keychain (written by Claude Code)

2. Discovers your connectors via api.anthropic.com/v1/mcp_servers

3. Connects to each via mcp-proxy.anthropic.com (Streamable HTTP)

4. Exposes all tools over stdio MCP protocol

Prerequisites

• Claude Code logged in (claude --version)

• Connectors authorized at https://claude.ai/settings/connectors

• Bun runtime (bun -v)

Quick start

1. Clone and install

git clone https://github.com/kitimark/claudeai-mcp-bridge.git
cd claudeai-mcp-bridge
bun install

2. Verify it works

bun run src/poc-discover.ts

You should see your connectors and their tools listed:

[claudeai-mcp] Found 5 connector(s):
[claudeai-mcp]   - Slack (id: mcpsrv_0...)
[claudeai-mcp]   - Atlassian (id: mcpsrv_0...)
[claudeai-mcp] --- Slack ---
[claudeai-mcp]   Tools (13):
[claudeai-mcp]     - slack_send_message: Sends a message to a Slack channel...

For TypeScript validation in this repo, use project-mode checks:

bun run typecheck

3. Add to your MCP client

OpenCode

// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "claudeai": {
      "type": "local",
      "command": ["bun", "run", "/absolute/path/to/claudeai-mcp-bridge/src/server.ts"]
    }
  }
}

Claude Desktop

// ~/Library/Application Support/Claude/claude_desktop_config.json
{
  "mcpServers": {
    "claudeai": {
      "command": "bun",
      "args": ["run", "/absolute/path/to/claudeai-mcp-bridge/src/server.ts"]
    }
  }
}

Cursor

// .cursor/mcp.json
{
  "mcpServers": {
    "claudeai": {
      "command": "bun",
      "args": ["run", "/absolute/path/to/claudeai-mcp-bridge/src/server.ts"],
      "env": {
        "CLAUDEAI_MCP_EXCLUDE": "Gmail,Google Calendar"
      }
    }
  }
}

4. Use it

> search slack for messages about the deployment from yesterday

> what are my open jira issues?

> find the confluence page about onboarding

Available tools

Once connected, you get the same tools as Claude Code:

Tool names follow the pattern: {connector}_{tool_name}

Examples: slack_search_public, atlassian_getJiraIssue

(Your MCP client may add its own prefix, e.g. OpenCode: claudeai_slack_search_public)

Configuration

Environment variables

Managing tools (OpenCode)

Disable specific connectors:

{ "tools": { "claudeai_atlassian_*": false } }

Enable only for specific agents:

{
  "tools": { "claudeai_*": false },
  "agent": {
    "slack-agent": { "tools": { "claudeai_slack_*": true } }
  }
}

Troubleshooting

Compatibility

How it compares to Claude Code

Docs

• ideas/how-it-works.md -- Full protocol research, architecture diagrams, source code analysis

• ideas/setup-guide.md -- Detailed setup guide with troubleshooting

Caveats

• Uses undocumented Anthropic endpoints (/v1/mcp_servers, mcp-proxy.anthropic.com) that may change

• Using Claude subscription tokens outside official clients may violate Anthropic's ToS

• Token refresh depends on Claude Code -- keep it installed

• macOS Keychain primary; Linux/Windows falls back to ~/.claude/.credentials.json

License

MIT