feat(rdesign): deploy KiCad & FreeCAD MCP as Docker sidecars

Switch from broken StdioClientTransport (child process) to
SSEClientTransport (HTTP to sidecar containers via supergateway).
Both sidecars share rspace-files volume so generated CAD files
(STEP, STL, Gerber, SVG) are directly servable without copying.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docker-compose.yml

@@ -262,6 +262,26 @@ services:
       retries: 5
       start_period: 10s
 
+  # ── KiCad MCP sidecar (PCB design via SSE) ──
+  kicad-mcp:
+    build: ./docker/kicad-mcp
+    container_name: kicad-mcp
+    restart: unless-stopped
+    volumes:
+      - rspace-files:/data/files
+    networks:
+      - rspace-internal
+
+  # ── FreeCAD MCP sidecar (3D CAD via SSE) ──
+  freecad-mcp:
+    build: ./docker/freecad-mcp
+    container_name: freecad-mcp
+    restart: unless-stopped
+    volumes:
+      - rspace-files:/data/files
+    networks:
+      - rspace-internal
+
   # ── Scribus noVNC (rDesign DTP workspace) ──
   scribus-novnc:
     build:

docker/freecad-mcp/Dockerfile

@@ -0,0 +1,27 @@
+FROM node:20-slim
+
+# Install FreeCAD headless (freecad-cmd) and dependencies
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    freecad \
+    ca-certificates \
+    && rm -rf /var/lib/apt/lists/*
+
+# Set headless Qt/FreeCAD env
+ENV QT_QPA_PLATFORM=offscreen
+ENV DISPLAY=""
+ENV FREECAD_USER_CONFIG=/tmp/.FreeCAD
+
+WORKDIR /app
+
+# Copy MCP server source
+COPY freecad-mcp-server/ .
+
+# Install Node deps + supergateway (stdio→SSE bridge)
+RUN npm install && npm install -g supergateway
+
+# Ensure generated files dir exists
+RUN mkdir -p /data/files/generated
+
+EXPOSE 8808
+
+CMD ["supergateway", "--stdio", "node build/index.js", "--port", "8808"]

docker/kicad-mcp/Dockerfile

@@ -0,0 +1,31 @@
+FROM node:20-slim
+
+# Install KiCad, Python, and build dependencies
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    kicad \
+    python3 \
+    python3-pip \
+    python3-venv \
+    ca-certificates \
+    && rm -rf /var/lib/apt/lists/*
+
+# Use SWIG backend (headless — no KiCad GUI needed)
+ENV KICAD_BACKEND=swig
+
+WORKDIR /app
+
+# Copy MCP server source
+COPY KiCAD-MCP-Server/ .
+
+# Install Node deps + supergateway (stdio→SSE bridge)
+RUN npm install && npm install -g supergateway
+
+# Install Python requirements (Pillow, cairosvg, etc.)
+RUN pip3 install --break-system-packages -r python/requirements.txt
+
+# Ensure generated files dir exists
+RUN mkdir -p /data/files/generated
+
+EXPOSE 8809
+
+CMD ["supergateway", "--stdio", "node dist/index.js", "--port", "8809"]

server/cad-orchestrator.ts

@@ -283,7 +283,7 @@ function extractPathFromText(text: string, extensions: string[]): string | null
 export const KICAD_SYSTEM_PROMPT = `You are a KiCad PCB design assistant. You have access to KiCad MCP tools to create real PCB designs.
 
 Follow this workflow:
-1. create_project — Create a new KiCad project in /tmp/kicad-gen-<timestamp>/
+1. create_project — Create a new KiCad project in /data/files/generated/kicad-<timestamp>/
 2. search_symbols — Find component symbols in KiCad libraries (e.g. ESP32, BME280, capacitors, resistors)
 3. add_schematic_component — Place each component on the schematic
 4. add_schematic_net_label — Add net labels for connections
@@ -296,7 +296,7 @@ Follow this workflow:
 11. export_gerber, export_bom, export_pdf — Generate manufacturing outputs
 
 Important:
-- Use /tmp/kicad-gen-${Date.now()}/ as the project directory
+- Use /data/files/generated/kicad-${Date.now()}/ as the project directory
 - Search for real symbols before placing components
 - Add decoupling capacitors and pull-up resistors as needed
 - Set reasonable board outline dimensions
@@ -307,16 +307,16 @@ Important:
 export const FREECAD_SYSTEM_PROMPT = `You are a FreeCAD parametric CAD assistant. You have access to FreeCAD MCP tools to create real 3D models.
 
 Follow this workflow:
-1. execute_python_script — Create output directory: import os; os.makedirs("/tmp/freecad-gen-<timestamp>", exist_ok=True)
+1. execute_python_script — Create output directory: import os; os.makedirs("/data/files/generated/freecad-<timestamp>", exist_ok=True)
 2. Create base geometry using create_box, create_cylinder, or create_sphere
 3. Use boolean_operation (union, cut, intersection) to combine shapes
 4. list_objects to verify the model state
 5. save_document to save the FreeCAD file
-6. execute_python_script to export STEP: Part.export([obj], "/tmp/freecad-gen-<id>/model.step")
+6. execute_python_script to export STEP: Part.export([obj], "/data/files/generated/freecad-<id>/model.step")
-7. execute_python_script to export STL: Mesh.export([obj], "/tmp/freecad-gen-<id>/model.stl")
+7. execute_python_script to export STL: Mesh.export([obj], "/data/files/generated/freecad-<id>/model.stl")
 
 Important:
-- Use /tmp/freecad-gen-${Date.now()}/ as the working directory
+- Use /data/files/generated/freecad-${Date.now()}/ as the working directory
 - For hollow objects, create the outer shell then cut the inner volume
 - For complex shapes, build up from primitives with boolean operations
 - Wall thickness should be at least 1mm for 3D printing

server/index.ts

@@ -1145,20 +1145,6 @@ async function process3DGenJob(job: Gen3DJob) {
 
 // ── Image helpers ──
 
-/** Copy a file from a tmp path to the served generated directory → return server-relative URL */
-async function copyToServed(srcPath: string): Promise<string | null> {
-	try {
-		const srcFile = Bun.file(srcPath);
-		if (!(await srcFile.exists())) return null;
-		const basename = srcPath.split("/").pop() || `file-${Date.now()}`;
-		const dir = resolve(process.env.FILES_DIR || "./data/files", "generated");
-		await Bun.write(resolve(dir, basename), srcFile);
-		return `/data/files/generated/${basename}`;
-	} catch {
-		return null;
-	}
-}
-
 /** Read a /data/files/generated/... path from disk → base64 */
 async function readFileAsBase64(serverPath: string): Promise<string> {
 	const filename = serverPath.split("/").pop();
@@ -1653,22 +1639,18 @@ app.post("/api/blender-gen", async (c) => {
 	}
 });
 
-// KiCAD PCB design — MCP stdio bridge
+// KiCAD PCB design — MCP SSE bridge (sidecar container)
 import { Client } from "@modelcontextprotocol/sdk/client/index.js";
-import { StdioClientTransport } from "@modelcontextprotocol/sdk/client/stdio.js";
+import { SSEClientTransport } from "@modelcontextprotocol/sdk/client/sse.js";
 import { runCadAgentLoop, assembleKicadResult, assembleFreecadResult, KICAD_SYSTEM_PROMPT, FREECAD_SYSTEM_PROMPT } from "./cad-orchestrator";
 
-const KICAD_MCP_PATH = process.env.KICAD_MCP_PATH || "/home/jeffe/KiCAD-MCP-Server/dist/index.js";
+const KICAD_MCP_URL = process.env.KICAD_MCP_URL || "http://kicad-mcp:8809/sse";
 let kicadClient: Client | null = null;
 
 async function getKicadClient(): Promise<Client> {
 	if (kicadClient) return kicadClient;
 
-	const transport = new StdioClientTransport({
+	const transport = new SSEClientTransport(new URL(KICAD_MCP_URL));
-		command: "node",
-		args: [KICAD_MCP_PATH],
-	});
-
 	const client = new Client({ name: "rspace-kicad-bridge", version: "1.0.0" });
 
 	transport.onclose = () => { kicadClient = null; };
@@ -1705,21 +1687,7 @@ app.post("/api/kicad/generate", async (c) => {
 		const orch = await runCadAgentLoop(client, KICAD_SYSTEM_PROMPT, enrichedPrompt, GEMINI_API_KEY);
 		const result = assembleKicadResult(orch);
 
-		// Copy generated files to served directory
+		// Files are already on the shared /data/files volume — no copy needed
-		const filesToCopy = [
-			{ path: result.schematicSvg, key: "schematicSvg" },
-			{ path: result.boardSvg, key: "boardSvg" },
-			{ path: result.gerberUrl, key: "gerberUrl" },
-			{ path: result.bomUrl, key: "bomUrl" },
-			{ path: result.pdfUrl, key: "pdfUrl" },
-		];
-
-		for (const { path, key } of filesToCopy) {
-			if (path && path.startsWith("/tmp/")) {
-				const served = await copyToServed(path);
-				if (served) (result as any)[key] = served;
-			}
-		}
 
 		return c.json({
 			schematic_svg: result.schematicSvg,
@@ -1774,18 +1742,14 @@ app.post("/api/kicad/:action", async (c) => {
 	}
 });
 
-// FreeCAD parametric CAD — MCP stdio bridge
+// FreeCAD parametric CAD — MCP SSE bridge (sidecar container)
-const FREECAD_MCP_PATH = process.env.FREECAD_MCP_PATH || "/home/jeffe/freecad-mcp-server/build/index.js";
+const FREECAD_MCP_URL = process.env.FREECAD_MCP_URL || "http://freecad-mcp:8808/sse";
 let freecadClient: Client | null = null;
 
 async function getFreecadClient(): Promise<Client> {
 	if (freecadClient) return freecadClient;
 
-	const transport = new StdioClientTransport({
+	const transport = new SSEClientTransport(new URL(FREECAD_MCP_URL));
-		command: "node",
-		args: [FREECAD_MCP_PATH],
-	});
-
 	const client = new Client({ name: "rspace-freecad-bridge", version: "1.0.0" });
 
 	transport.onclose = () => { freecadClient = null; };
@@ -1818,14 +1782,7 @@ app.post("/api/freecad/generate", async (c) => {
 		const orch = await runCadAgentLoop(client, FREECAD_SYSTEM_PROMPT, prompt, GEMINI_API_KEY);
 		const result = assembleFreecadResult(orch);
 
-		// Copy generated files to served directory
+		// Files are already on the shared /data/files volume — no copy needed
-		for (const key of ["stepUrl", "stlUrl"] as const) {
-			const path = result[key];
-			if (path && path.startsWith("/tmp/")) {
-				const served = await copyToServed(path);
-				if (served) (result as any)[key] = served;
-			}
-		}
 
 		return c.json({
 			preview_url: result.previewUrl,