a2n.EasyEDA MCP

Pure-interface MCP bridge for EasyEDA Pro. No AI, no API keys, no external server. It exposes the EasyEDA eda.* API to any MCP client (Claude, Codex, and other MCP-compatible agents) so the client's own model drives schematic/PCB automation directly.

Merged from the best of two open-source projects:

• Low-level eda.* coverage (PCB primitives, tracks, vias, nets, DRC, layers, pads, pour/fill, manufacture exports, schematic primitives) — inspired by QuincySx/easyeda-agent-mcp-server.
• High-level project/document/checkpoint handling and a local auto-place + auto-wire engine (sch_assemble_circuit) — inspired by biosshot/easyeda-copilot (server/AI parts removed).

Features

• Pure interface to EasyEDA Pro — the bridge holds no model and needs no API key.
• Full low-level schematic and PCB control plus high-level circuit assembly.
• Configurable WebSocket port and online / offline / hybrid component sourcing.
• Self-contained MCP server (single bundled file) and a packaged .eext extension.

Architecture

flowchart LR
    Client["MCP Client<br/>(Claude, Codex, ...)"]
    Server["a2n MCP Server<br/>(Node.js, stdio)"]
    Ext["a2n EasyEDA Extension"]
    EDA[("EasyEDA Pro<br/>eda.* API")]

    Client -- "stdio (MCP)" --> Server
    Server -- "WebSocket :8788" --> Ext
    Ext -- "eda.* calls" --> EDA
    EDA -- "results" --> Ext
    Ext -- "WebSocket" --> Server
    Server -- "tool result" --> Client

• MCP server (src/mcp-server): runs locally, opens a WebSocket server on a configurable port (default 8788), exposes the MCP tools.
• EasyEDA extension (src/extension): connects to the WebSocket server, executes eda.* calls, returns results. Adds an a2n MCP menu (Connect / Disconnect / Configure / Status / About).

Request flow

sequenceDiagram
    participant C as MCP Client
    participant S as a2n MCP Server
    participant X as EasyEDA Extension
    participant E as EasyEDA Pro

    C->>S: Tool call (e.g. sch_assemble_circuit)
    S->>X: WebSocket request { method, params }
    X->>E: eda.* API calls
    E-->>X: API result
    X-->>S: WebSocket response { result | error }
    S-->>C: Tool result

Modes (online / offline / hybrid)

Configured in the extension (a2n MCP -> Configure...):

flowchart TD
    Q["sch_search_component"] --> M{Mode}
    M -- offline --> L["Local / system libraries only"]
    M -- online --> O["EasyEDA backend search<br/>(lib_Device.search, devices/searchByCodes)"]
    M -- hybrid --> H["Try local first"]
    H --> F{Found?}
    F -- yes --> R["Return local results"]
    F -- no --> O

• offline — component search restricted to local/system libraries.
• online — component search via the EasyEDA backend. Uses your existing EasyEDA login; no extra API key.
• hybrid — local first, then online fallback (default).

Build

npm install
npm run build      # builds the extension (dist/index.js) + MCP server (dist/mcp-server) and packages the .eext
# or just:
npm run compile    # builds without packaging the .eext

Outputs:

• dist/mcp-server/index.js — the MCP server (self-contained, runnable with Node).
• build/dist/a2n-easyeda-mcp_v<version>.eext — import into EasyEDA Pro (Settings -> Extensions -> Extensions Manager -> Import Extensions).

MCP client configuration

Recommended (after publishing to npm):

{
  "mcpServers": {
    "a2n-easyeda-mcp": {
      "command": "npx",
      "args": ["-y", "a2n-easyeda-mcp"]
    }
  }
}

Local build (without npm):

{
  "mcpServers": {
    "a2n-easyeda-mcp": {
      "command": "node",
      "args": ["<abs-path>/a2n-easyeda-mcp/dist/mcp-server/index.js", "--port=8788"]
    }
  }
}

The default port is 8788 and matches on both sides, so --port is optional unless you change it. Override with --port=NNNN or the A2N_EDA_WS_PORT environment variable.

Usage

flowchart LR
    A["Import .eext into<br/>EasyEDA Pro"] --> B["Enable<br/>External Interactions"]
    B --> C["a2n MCP -> Connect MCP"]
    C --> D["Start MCP client<br/>with this server"]
    D --> E["Call eda_status<br/>to confirm"]

1. Build and import the .eext into EasyEDA Pro; enable "External Interactions".
2. Open a schematic/PCB, then a2n MCP -> Connect MCP (set the port via Configure... if you changed it).
3. Start your MCP client with this server configured, then call eda_status to confirm the connection and active mode.

The WebSocket port must match on both sides (server --port / A2N_EDA_WS_PORT and the extension's Configure dialog).

License

MIT. This project is a derivative work that reuses and adapts code from the MIT-licensed projects QuincySx/easyeda-agent-mcp-server and biosshot/easyeda-copilot; their respective copyrights are retained under the same license.