mcp-ppsspp

An MCP server that exposes PPSSPP — the PlayStation Portable emulator — to any MCP-compatible client (Claude Desktop, Claude Code, etc.) via PPSSPP's built-in WebSocket debugger interface.

Read and write PSP memory, drive games with button input, capture screenshots, set CPU breakpoints, inspect MIPS Allegrex registers — all through a clean tool interface. No bridge plugin needed; PPSSPP's debugger is built into the emulator.

How it works

+------------------+    stdio     +------------------+   WebSocket    +------------------+
|   MCP client     |   JSON-RPC   |    mcp-ppsspp    |   JSON-RPC     |     PPSSPP       |
| (Claude / etc.)  | ===========> |     (Node.js)    | =============> |    (debugger)    |
+------------------+              +------------------+                +------------------+

Unlike the mcp-bizhawk / mcp-mgba bridges (which need a Lua plugin loaded into the emulator), PPSSPP ships with its own debugger WebSocket interface — we just speak JSON to it. No plugin to install.

The connection uses subprotocol debugger.ppsspp.org on PPSSPP's debugger port.

Requirements

• PPSSPP (recent version with WebSocket debugger — 1.7+)

• Node.js 18+

• "Allow remote debugger" enabled in PPSSPP

Install

npm install -g mcp-ppsspp

Or npx -y mcp-ppsspp.

Set up PPSSPP's debugger

1. Launch PPSSPP, load any PSP ISO/EBOOT

2. Settings → Tools → Developer Tools → Allow remote debugger (check the box)

3. PPSSPP will show the active host:port (e.g. ws://192.168.1.10:12345/debugger)

4. Note the port number — you'll set it as an environment variable for the MCP server

Register with your MCP client

Claude Code (CLI)

claude mcp add ppsspp --scope user --env PPSSPP_PORT=12345 mcp-ppsspp

Replace 12345 with your actual port. Verify:

claude mcp list
# ppsspp: mcp-ppsspp - ✓ Connected

Claude Desktop

Edit claude_desktop_config.json:

{
  "mcpServers": {
    "ppsspp": {
      "command": "mcp-ppsspp",
      "env": { "PPSSPP_PORT": "12345" }
    }
  }
}

Restart Claude Desktop after editing.

Configuration

Tools

PSP memory map (cheat sheet)

PSP is little-endian (MIPS Allegrex). Kernel-mode mirrors at 0x88xxxxxx map to the same physical RAM as 0x08xxxxxx.

PSP buttons

cross, circle, triangle, square, up, down, left, right, start, select, ltrigger, rtrigger, home.

Troubleshooting

Limitations

• No savestate API — PPSSPP's WebSocket debugger doesn't expose savestate.save / load. Use PPSSPP's keybinds (F1-F8 for slots) via the UI for now. Could be hacked by using input.buttons.press to trigger the keybind, but not native.

• Frame-advance is instruction-level only (cpu.stepInto). To advance a whole frame, set a breakpoint at the vblank handler and resume.

• Analog stick is shared state — ppsspp_send_analog updates the persistent stick position; not auto-released.

Development

npm install
npm run dev      # tsc --watch — autobuilds on src/ changes

License

MIT