Transport

The protocol stays transport-agnostic. The current reference implementation ships two MDP-side transports:

• ws / wss for direct bidirectional sessions
• http / https loop mode for runtimes that prefer request/response polling

Transport auth is independent from the message set. In the reference server it can arrive:

• directly in Authorization, Cookie, or x-mdp-auth-* headers
• through POST /mdp/auth, which issues an auth cookie that the browser can carry into a later ws / wss upgrade

Both transports preserve the same message model:

• registerClient
• unregisterClient
• callClient
• callClientResult
• ping
• pong

That means registry, routing, and MCP bridge logic stay unchanged when the transport changes.