MCPFlo implements a deliberately focused set of MCP transports rather than supporting every transport the protocol has ever defined. This page is the reference for what’s supported today.

Supported

stdio For local MCP servers spawned as a child process. MCPFlo manages the process lifecycle (spawn, cleanup on remove/quit). See Adding a Server.

Streamable HTTP For remote (or already-running) MCP servers exposed over HTTP. Supports custom request headers and OAuth 2.1 authentication. See Adding a Server and Authentication & OAuth 2.1.

Not supported

HTTP+SSE (deprecated transport) The older HTTP+SSE transport — superseded by Streamable HTTP in the MCP spec — is intentionally not implemented. If you’re connecting to a server that only speaks SSE and not Streamable HTTP, it currently cannot be added to MCPFlo.

This is a deliberate scope decision, not an oversight: Streamable HTTP is the protocol’s current recommended transport for remote servers, and supporting the deprecated variant alongside it would add complexity for a transport most servers have already moved away from.

What to do if your server only supports SSE

• Check whether the server (or a newer version of it) supports Streamable HTTP instead — many actively maintained MCP servers have migrated.
• If you maintain the server yourself, consider adding Streamable HTTP support alongside (or instead of) SSE.

Related

• See Adding a Server for how to configure each supported transport.
• See the “Not supported” list in Platform Notes for other deliberate scope limitations (no persistent history, macOS arm64-only).