External MCP Servers
Connect remote MCP-compatible servers to extend FlowTrux with custom tools
FlowTrux can connect to remote MCP-compatible servers, not just the built-in ones. This lets you integrate custom tools, internal APIs, or third-party MCP servers into your workflows.
Availability: External servers may not be enabled in every deployment. If the External option is not shown when adding an MCP server, contact your operator or support.
How External Servers Work
An external MCP server is a remote server that:
- Is reachable over HTTPS at a URL you provide.
- Implements the MCP protocol with the Streamable HTTP transport to advertise tools and handle tool calls.
FlowTrux connects to the server over HTTPS, discovers its tools, and makes them available to Agent and Action nodes the same way as built-in server tools.
Adding an External Server
- Go to Settings > MCP Servers > Add Server.
- Select External.
- Configure the server:
| Field | Required | Description |
|---|---|---|
| Name | Yes | Display name for the server |
| URL | Yes | HTTPS endpoint of the remote MCP server |
| Authentication | Yes | One of: Bearer token, API key header (custom header name, default X-API-Key), or None |
| Extra headers | No | Additional non-secret headers sent with every request |
- Click Save.
- Assign to a workspace in Settings > Workspaces > Edit.
Security
- Secrets (bearer tokens, API keys) are encrypted at rest, the same way built-in server credentials are stored.
- Extra headers are intended for non-secret values (e.g., a tenant or region identifier) - put secrets in the authentication fields instead.
- Connections are made over HTTPS only.
Building Your Own MCP Server
To connect your own server to FlowTrux, implement an MCP server with the Streamable HTTP transport:
- Expose an HTTPS endpoint that speaks the MCP protocol.
- Advertise your tools with names, descriptions, and input schemas.
- Handle tool calls and return results.
The official MCP SDKs (TypeScript, Python, and others) include a Streamable HTTP server transport that handles the protocol boilerplate. See the MCP specification and SDK documentation for details.