feat(cowork): re-enable Claude Cowork with preset-only stdio MCP

Restore Cowork feature while closing the RCE vector: drop user-defined
stdio commands so only hard-coded preset plugins (browsermcp) may spawn.
Custom MCP now accepts remote URL only. Routes stay gated to localhost.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/app/(dashboard)/dashboard/cli-tools/components/CoworkToolCard.js

@@ -48,7 +48,7 @@ export default function CoworkToolCard({
   const [modelSelectOpen, setModelSelectOpen] = useState(false);
   const [marketplaceOpen, setMarketplaceOpen] = useState(false);
   const [addMcpOpen, setAddMcpOpen] = useState(false);
-  const [addMcpForm, setAddMcpForm] = useState({ type: "url", name: "", url: "", command: "", args: "" });
+  const [addMcpForm, setAddMcpForm] = useState({ name: "", url: "" });
 
   useEffect(() => {
     if (apiKeys?.length > 0 && !selectedApiKey) {
@@ -374,7 +374,7 @@ export default function CoworkToolCard({
                       <div key={p.name} className="flex items-center gap-2 px-2 py-1 bg-surface rounded border border-border">
                         <span className="text-xs font-medium min-w-0 truncate flex-shrink-0">{p.name}</span>
                         <span className="text-[8px] px-1 py-0.5 rounded bg-blue-500/10 text-blue-500 shrink-0">custom</span>
-                        <span className="flex-1 text-[9px] text-text-muted truncate">{p.url || p.command}</span>
+                        <span className="flex-1 text-[9px] text-text-muted truncate">{p.url}</span>
                         <button onClick={() => setCustomPlugins(customPlugins.filter((x) => x.name !== p.name))} className="shrink-0 hover:text-red-500 ml-auto">
                           <span className="material-symbols-outlined text-[12px]">close</span>
                         </button>
@@ -388,7 +388,7 @@ export default function CoworkToolCard({
                       <button onClick={() => setMarketplaceOpen(true)} className="px-2 py-1 rounded border text-xs bg-primary/10 border-primary/40 text-primary hover:bg-primary/20 cursor-pointer whitespace-nowrap">
                         + Browse
                       </button>
-                      <button onClick={() => { setAddMcpForm({ type: "url", name: "", url: "", command: "", args: "" }); setAddMcpOpen(true); }} className="px-2 py-1 rounded border text-xs bg-surface border-border text-text-muted hover:border-primary hover:text-primary cursor-pointer whitespace-nowrap">
+                      <button onClick={() => { setAddMcpForm({ name: "", url: "" }); setAddMcpOpen(true); }} className="px-2 py-1 rounded border text-xs bg-surface border-border text-text-muted hover:border-primary hover:text-primary cursor-pointer whitespace-nowrap">
                         + Custom
                       </button>
                       <a href="https://mcp.so" target="_blank" rel="noopener noreferrer" className="text-[10px] text-text-muted hover:text-primary underline ml-auto">Find MCPs →</a>
@@ -554,17 +554,6 @@ export default function CoworkToolCard({
               </button>
             </div>
 
-            <div className="flex gap-2">
-              <button
-                onClick={() => setAddMcpForm((f) => ({ ...f, type: "url" }))}
-                className={`flex-1 py-1.5 rounded border text-xs font-medium transition-colors ${addMcpForm.type === "url" ? "bg-primary/10 border-primary/40 text-primary" : "border-border text-text-muted hover:border-primary/40"}`}
-              >URL (SSE)</button>
-              <button
-                onClick={() => setAddMcpForm((f) => ({ ...f, type: "cmd" }))}
-                className={`flex-1 py-1.5 rounded border text-xs font-medium transition-colors ${addMcpForm.type === "cmd" ? "bg-primary/10 border-primary/40 text-primary" : "border-border text-text-muted hover:border-primary/40"}`}
-              >Command (stdio)</button>
-            </div>
-
             <div className="flex flex-col gap-2">
               <div className="flex flex-col gap-1">
                 <label className="text-[11px] text-text-muted font-medium">Name</label>
@@ -576,7 +565,6 @@ export default function CoworkToolCard({
                   className="px-2 py-1.5 rounded border border-border bg-surface text-xs outline-none focus:border-primary"
                 />
               </div>
-              {addMcpForm.type === "url" ? (
               <div className="flex flex-col gap-1">
                 <label className="text-[11px] text-text-muted font-medium">SSE URL</label>
                 <input
@@ -587,30 +575,6 @@ export default function CoworkToolCard({
                   className="px-2 py-1.5 rounded border border-border bg-surface text-xs outline-none focus:border-primary"
                 />
               </div>
-              ) : (
-                <>
-                  <div className="flex flex-col gap-1">
-                    <label className="text-[11px] text-text-muted font-medium">Command</label>
-                    <input
-                      type="text"
-                      placeholder="npx"
-                      value={addMcpForm.command}
-                      onChange={(e) => setAddMcpForm((f) => ({ ...f, command: e.target.value }))}
-                      className="px-2 py-1.5 rounded border border-border bg-surface text-xs outline-none focus:border-primary"
-                    />
-                  </div>
-                  <div className="flex flex-col gap-1">
-                    <label className="text-[11px] text-text-muted font-medium">Args <span className="font-normal">(comma-separated)</span></label>
-                    <input
-                      type="text"
-                      placeholder="-y, @some/mcp-package"
-                      value={addMcpForm.args}
-                      onChange={(e) => setAddMcpForm((f) => ({ ...f, args: e.target.value }))}
-                      className="px-2 py-1.5 rounded border border-border bg-surface text-xs outline-none focus:border-primary"
-                    />
-                  </div>
-                </>
-              )}
             </div>
 
             <div className="flex gap-2 justify-end">
@@ -618,15 +582,8 @@ export default function CoworkToolCard({
               <button
                 onClick={() => {
                   const name = addMcpForm.name.trim();
-                  if (!name) return;
+                  if (!name || !addMcpForm.url.trim()) return;
-                  if (addMcpForm.type === "url") {
-                    if (!addMcpForm.url.trim()) return;
                   setCustomPlugins((prev) => [...prev.filter((x) => x.name !== name), { name, url: addMcpForm.url.trim(), transport: "sse", custom: true }]);
-                  } else {
-                    if (!addMcpForm.command.trim()) return;
-                    const args = addMcpForm.args.split(",").map((a) => a.trim()).filter(Boolean);
-                    setCustomPlugins((prev) => [...prev.filter((x) => x.name !== name), { name, command: addMcpForm.command.trim(), args, custom: true }]);
-                  }
                   setAddMcpOpen(false);
                 }}
                 className="px-3 py-1.5 rounded bg-primary text-white text-xs font-medium hover:opacity-90 cursor-pointer"

src/app/api/cli-tools/cowork-settings/route.js

@@ -5,9 +5,8 @@ import fs from "fs/promises";
 import path from "path";
 import os from "os";
 import crypto from "crypto";
-import { DEFAULT_PLUGINS, LOCAL_STDIO_PLUGINS, ALLOWED_MCP_COMMANDS, buildManagedMcpServers } from "@/shared/constants/coworkPlugins";
+import { DEFAULT_PLUGINS, LOCAL_STDIO_PLUGINS, buildManagedMcpServers } from "@/shared/constants/coworkPlugins";
 import { UPDATER_CONFIG } from "@/shared/constants/config";
-import { DATA_DIR } from "@/lib/dataDir";
 import { getConsistentMachineId } from "@/shared/utils/machineId";
 
 const APP_PORT = UPDATER_CONFIG.appPort;
@@ -180,17 +179,8 @@ const buildCustomEntries = (customPlugins) => {
   if (!Array.isArray(customPlugins)) return [];
   const out = [];
   for (const p of customPlugins) {
-    if (!p?.name) continue;
+    if (!p?.name || !p?.url) continue;
-    if (p.url) {
     out.push({ name: p.name, url: p.url, transport: p.transport || "sse", custom: true });
-    } else if (p.command) {
-      out.push({
-        name: p.name,
-        url: `http://localhost:${APP_PORT}/api/mcp/${encodeURIComponent(p.name)}/sse`,
-        transport: "sse",
-        custom: true,
-      });
-    }
   }
   return out;
 };
@@ -311,8 +301,6 @@ export async function GET() {
 }
 
 export async function POST(request) {
-  // Cowork disabled: spawns arbitrary processes (RCE risk).
-  return NextResponse.json({ error: "Cowork is disabled" }, { status: 403 });
   try {
     const { baseUrl, apiKey, models, plugins, localPlugins, customPlugins } = await request.json();
 
@@ -327,29 +315,8 @@ export async function POST(request) {
     // Respect empty array (user toggled all off); fallback to defaults only when undefined.
     const pluginsArray = Array.isArray(plugins) ? plugins : DEFAULT_PLUGINS;
     const localPluginNames = Array.isArray(localPlugins) ? localPlugins : [];
-    const customPluginsArray = Array.isArray(customPlugins) ? customPlugins : [];
+    // Only URL-based custom plugins allowed (no stdio command spawning).
-
+    const customPluginsArray = (Array.isArray(customPlugins) ? customPlugins : []).filter((p) => p?.url);
-    // Register custom stdio plugins into bridge + persist for restart survival.
-    if (customPluginsArray.length > 0) {
-      const { registerCustomPlugin } = require("@/lib/mcp/stdioSseBridge");
-      const stdioCustoms = customPluginsArray
-        .filter((p) => p && typeof p.command === "string" && p.command.trim())
-        .filter((p) => ALLOWED_MCP_COMMANDS.has(path.basename(p.command)))
-        .map((p) => ({
-          name: String(p.name || "").replace(/[^a-zA-Z0-9_-]/g, "").slice(0, 64),
-          command: p.command,
-          args: Array.isArray(p.args) ? p.args.map(String) : [],
-        }))
-        .filter((p) => p.name);
-      for (const p of stdioCustoms) {
-        try { registerCustomPlugin(p); } catch { /* skip invalid */ }
-      }
-      try {
-        const dir = path.join(DATA_DIR, "mcp");
-        await fs.mkdir(dir, { recursive: true });
-        await fs.writeFile(path.join(dir, "customPlugins.json"), JSON.stringify(stdioCustoms, null, 2));
-      } catch { /* ignore */ }
-    }
 
     const bridgeEntries = await injectAuthHeaders(buildLocalBridgeEntries(localPluginNames));
     const customEntries = await injectAuthHeaders(buildCustomEntries(customPluginsArray));

src/app/api/mcp/[plugin]/message/route.js

@@ -5,8 +5,6 @@ export const runtime = "nodejs";
 export const dynamic = "force-dynamic";
 
 export async function POST(request, { params }) {
-  // Cowork disabled: MCP stdio bridge spawns arbitrary processes (RCE risk).
-  return NextResponse.json({ error: "Cowork is disabled" }, { status: 403 });
   const { plugin } = await params;
   if (!findPlugin(plugin)) {
     return NextResponse.json({ error: `Unknown plugin: ${plugin}` }, { status: 404 });

src/app/api/mcp/[plugin]/sse/route.js

@@ -4,8 +4,6 @@ export const runtime = "nodejs";
 export const dynamic = "force-dynamic";
 
 export async function GET(request, { params }) {
-  // Cowork disabled: MCP stdio bridge spawns arbitrary processes (RCE risk).
-  return new Response("Cowork is disabled", { status: 403 });
   const { plugin } = await params;
   if (!findPlugin(plugin)) {
     return new Response(`Unknown plugin: ${plugin}`, { status: 404 });

src/lib/mcp/stdioSseBridge.js

@@ -2,13 +2,8 @@
 // broadcasts JSON-RPC frames over SSE, accepts client messages via HTTP POST.
 
 const { spawn } = require("child_process");
-const fs = require("fs");
-const path = require("path");
 const crypto = require("crypto");
-const { LOCAL_STDIO_PLUGINS, ALLOWED_MCP_COMMANDS } = require("@/shared/constants/coworkPlugins");
+const { LOCAL_STDIO_PLUGINS } = require("@/shared/constants/coworkPlugins");
-const { DATA_DIR } = require("@/lib/dataDir");
-
-const CUSTOM_FILE = path.join(DATA_DIR, "mcp", "customPlugins.json");
 
 const G_KEY = "__9routerMcpBridges";
 const MAX_TEXT_CHARS = 50000;
@@ -106,33 +101,9 @@ const getStore = () => {
   return globalThis[G_KEY];
 };
 
-const getCustomStore = () => {
+// Only preset stdio plugins may spawn. No user-defined commands (RCE prevention).
-  if (!globalThis.__9routerCustomPlugins) globalThis.__9routerCustomPlugins = new Map();
-  return globalThis.__9routerCustomPlugins;
-};
-
-function isAllowedCommand(cmd) {
-  const bin = path.basename(String(cmd || ""));
-  return ALLOWED_MCP_COMMANDS.has(bin);
-}
-
-function registerCustomPlugin(def) {
-  if (!isAllowedCommand(def?.command)) {
-    throw new Error(`Blocked: command '${def?.command}' not in MCP allowlist`);
-  }
-  getCustomStore().set(def.name, def);
-}
-
 function findPlugin(name) {
-  const fromMem = getCustomStore().get(name) || LOCAL_STDIO_PLUGINS.find((p) => p.name === name);
+  return LOCAL_STDIO_PLUGINS.find((p) => p.name === name) || null;
-  if (fromMem) return fromMem;
-  // Lazy-load custom plugins from disk (survives app restart); re-validate allowlist.
-  try {
-    const list = JSON.parse(fs.readFileSync(CUSTOM_FILE, "utf-8"));
-    const def = Array.isArray(list) ? list.find((p) => p.name === name && p.command) : null;
-    if (def && isAllowedCommand(def.command)) { getCustomStore().set(def.name, def); return def; }
-  } catch { /* file missing or invalid */ }
-  return null;
 }
 
 function getOrSpawn(name) {
@@ -195,4 +166,4 @@ function isRunning(name) {
   return !!(entry?.proc && !entry.proc.killed && entry.proc.exitCode === null);
 }
 
-module.exports = { getOrSpawn, registerSession, unregisterSession, sendToChild, isRunning, findPlugin, registerCustomPlugin };
+module.exports = { getOrSpawn, registerSession, unregisterSession, sendToChild, isRunning, findPlugin };

src/shared/constants/cliTools.js

@@ -128,15 +128,14 @@ export const CLI_TOOLS = {
     description: "OpenCode AI Terminal Assistant",
     configType: "custom",
   },
-  // Cowork disabled: spawns arbitrary processes (RCE risk). Hidden from CLI tools UI.
+  cowork: {
-  // cowork: {
+    id: "cowork",
-  //   id: "cowork",
+    name: "Claude Cowork",
-  //   name: "Claude Cowork",
+    image: "/providers/claude.png",
-  //   image: "/providers/claude.png",
+    color: "#D97757",
-  //   color: "#D97757",
+    description: "Claude Desktop Cowork (third-party inference)",
-  //   description: "Claude Desktop Cowork (third-party inference)",
+    configType: "custom",
-  //   configType: "custom",
+  },
-  // },
   hermes: {
     id: "hermes",
     name: "Hermes Agent",

src/shared/constants/coworkPlugins.js

@@ -69,7 +69,4 @@ function buildManagedMcpServers(plugins) {
   return out;
 }
 
-// Allowlist of executables that may be spawned for custom stdio MCP plugins.
+module.exports = { DEFAULT_PLUGINS, LOCAL_STDIO_PLUGINS, buildManagedMcpServers };
-const ALLOWED_MCP_COMMANDS = new Set(["npx", "node", "uvx", "python", "python3", "bunx", "bun"]);
-
-module.exports = { DEFAULT_PLUGINS, LOCAL_STDIO_PLUGINS, ALLOWED_MCP_COMMANDS, buildManagedMcpServers };