Implementation Overview

Symposium consists of several major components:

a MCP server, implemented in Rust (symposium/mcp-server), which also serves as an IPC bus;
a VSCode extension, implemented in TypeScript (symposium/vscode);
a desktop application, implemented in Swift (symposium/macos-app).

Chart

flowchart TD
    Agent
    User

    User -- makes requests --> Agent

    Agent -- invokes MCP tools --> MCP

    subgraph L [Symposium]
        IDE["IDE Extension
            (impl'd in TypeScript
            or lang appropriate for IDE)"]
        MCP["symposium-mcp server
            (impl'd in Rust)"]
        APP["Desktop application
            (impl'd in Swift)"]

        MCP <--> IDE
        MCP <--> APP
        IDE <--> APP
    end

    L -..- BUS
    BUS["All communication actually goes over a central IPC Bus"]

All components talk over an IPC bus which is implemented in symposium-mcp. The IDE + application connect to this bus by running symposium-mcp client. This will create a daemon process (using symposium-mcp server) if one is not already running. The MCP server just runs the code inline, starting the server if needed.

The client has a simple interface:

a message is a single-line of json;
each message that is sent is forwarded to all connected clients (including the sender);
there are some special "control" messages that begin with #, e.g.
- #identify:name sets the "id" for this client to "name"
- see handle_debug_command in daemon.rs

Debugging

The server tracks the last N messages that have been gone out over the bus for debugging purposes. You can run

symposium-mcp debug

to access those logs. Very useful!