Added support for HTTPS_PROXY / HTTP_PROXY / NO_PROXY env vars

README.md

@@ -967,6 +967,8 @@ Config files support environment variable substitution using `${VAR_NAME}` synta
 - `MCPC_HOME_DIR` - Directory for session and authentication profiles data (default is `~/.mcpc`)
 - `MCPC_VERBOSE` - Enable verbose logging (set to `1`, `true`, or `yes`, case-insensitive)
 - `MCPC_JSON` - Enable JSON output (set to `1`, `true`, or `yes`, case-insensitive)
+- `HTTPS_PROXY` / `https_proxy` / `HTTP_PROXY` / `http_proxy` - Proxy URL for outbound connections (e.g. `http://proxy.example.com:8080`); `HTTPS_PROXY` takes precedence
+- `NO_PROXY` / `no_proxy` - Comma-separated list of hostnames/IPs to bypass the proxy (e.g. `localhost,127.0.0.1`)
 
 ### Cleanup
 

package.json

@@ -4,11 +4,12 @@
   "description": "Universal command-line client for the Model Context Protocol (MCP).",
   "type": "module",
   "keywords": [
-    "mcp",
-    "model-context-protocol",
-    "cli",
-    "llm",
-    "ai"
+    "Model Context Protocol",
+    "MCP",
+    "CLI",
+    "Code mode",
+    "LLM",
+    "AI"
   ],
   "license": "Apache-2.0",
   "author": "Jan Curn (@jancurn)",
@@ -59,6 +60,7 @@
     "commander": "^14.0.2",
     "ora": "^9.0.0",
     "proper-lockfile": "^4.1.2",
+    "undici": "^7.22.0",
     "uuid": "^13.0.0"
   },
   "devDependencies": {
@@ -75,6 +77,7 @@
     "markdown-link-check": "^3.14.2",
     "nyc": "^18.0.0",
     "prettier": "^3.7.4",
+    "proxy-chain": "^2.7.1",
     "ts-jest": "^29.4.6",
     "typescript": "^5.9.3"
   }

src/bridge/index.ts

@@ -5,6 +5,7 @@
  * It communicates with the CLI via Unix domain sockets
  */
 
+import { EnvHttpProxyAgent, setGlobalDispatcher } from 'undici';
 import { createServer, type Server as NetServer, type Socket } from 'net';
 import { unlink } from 'fs/promises';
 import { createMcpClient, CreateMcpClientOptions } from '../core/index.js';
@@ -35,6 +36,9 @@ const { version: mcpcVersion } = createRequire(import.meta.url)('../../package.j
 import { ProxyServer } from './proxy-server.js';
 import type { ProxyConfig } from '../lib/types.js';
 
+// Set up HTTP proxy from environment variables (HTTPS_PROXY, HTTP_PROXY, NO_PROXY, and lowercase variants)
+setGlobalDispatcher(new EnvHttpProxyAgent());
+
 // Keepalive ping interval in milliseconds (30 seconds)
 const KEEPALIVE_INTERVAL_MS = 30_000;
 

src/bridge/proxy-server.ts

@@ -12,6 +12,7 @@ import {
   type IncomingMessage,
   type ServerResponse,
 } from 'http';
+import { randomUUID } from 'crypto';
 import { Server as MCPServer } from '@modelcontextprotocol/sdk/server/index.js';
 import { StreamableHTTPServerTransport } from '@modelcontextprotocol/sdk/server/streamableHttp.js';
 import type { Transport } from '@modelcontextprotocol/sdk/shared/transport.js';
@@ -83,6 +84,12 @@ export class ProxyServer {
     // Register handlers that forward to upstream client
     this.registerHandlers(client);
 
+    // Create transport with session management and connect MCP server once
+    this.transport = new StreamableHTTPServerTransport({
+      sessionIdGenerator: () => randomUUID(),
+    });
+    await this.mcpServer.connect(this.transport as unknown as Transport);
+
     // Create HTTP server
     this.httpServer = createServer((req, res) => {
       this.handleRequest(req, res, bearerToken).catch((error) => {
@@ -146,27 +153,9 @@ export class ProxyServer {
       }
     }
 
-    // Handle MCP requests
-    if (method === 'POST') {
-      // Create transport for this request (stateless - no session management)
-      this.transport = new StreamableHTTPServerTransport({});
-
-      // Connect transport to MCP server (cast needed due to exactOptionalPropertyTypes)
-      await this.mcpServer!.connect(this.transport as unknown as Transport);
-
-      // Handle the request
-      await this.transport.handleRequest(req, res);
-      return;
-    }
-
-    // Handle GET for SSE (if needed)
-    if (method === 'GET') {
-      // Create transport for this request (stateless - no session management)
-      this.transport = new StreamableHTTPServerTransport({});
-
-      // Connect transport to MCP server (cast needed due to exactOptionalPropertyTypes)
-      await this.mcpServer!.connect(this.transport as unknown as Transport);
-      await this.transport.handleRequest(req, res);
+    // Handle MCP requests (POST and GET delegate to the transport)
+    if (method === 'POST' || method === 'GET') {
+      await this.transport!.handleRequest(req, res);
       return;
     }
 

src/cli/commands/sessions.ts

@@ -443,7 +443,7 @@ export async function closeSession(
 
     // Success!
     if (options.outputMode === 'human') {
-      console.log(formatSuccess(`Session ${name} closed successfully`));
+      console.log(formatSuccess(`Session ${name} closed successfully\n`));
     } else {
       console.log(
         formatOutput(

src/cli/index.ts

@@ -10,6 +10,7 @@
 /* eslint-disable @typescript-eslint/no-unsafe-member-access */
 /* eslint-disable @typescript-eslint/no-unsafe-argument */
 
+import { EnvHttpProxyAgent, setGlobalDispatcher } from 'undici';
 import { Command } from 'commander';
 import { setVerbose, setJsonMode, closeFileLogger } from '../lib/index.js';
 import { isMcpError, formatHumanError, NetworkError } from '../lib/index.js';
@@ -39,6 +40,9 @@ const { version: mcpcVersion } = createRequire(import.meta.url)('../../package.j
   version: string;
 };
 
+// Set up HTTP proxy from environment variables (HTTPS_PROXY, HTTP_PROXY, NO_PROXY, and lowercase variants)
+setGlobalDispatcher(new EnvHttpProxyAgent());
+
 /**
  * Options passed to command handlers
  */

test/e2e/lib/framework.sh

@@ -146,6 +146,14 @@ _test_cleanup() {
     done
   fi
 
+  # Stop proxy server if started
+  if [[ -n "${_PROXY_SERVER_PID:-}" ]]; then
+    pkill -P "$_PROXY_SERVER_PID" 2>/dev/null || true
+    kill "$_PROXY_SERVER_PID" 2>/dev/null || true
+    wait "$_PROXY_SERVER_PID" 2>/dev/null || true
+    _PROXY_SERVER_PID=""
+  fi
+
   # Clean up keychain entries for our sessions
   _cleanup_keychain
 
@@ -548,6 +556,7 @@ assert_stderr_empty() {
 # Default test server port
 TEST_SERVER_PORT="${TEST_SERVER_PORT:-0}"  # 0 = random port
 _TEST_SERVER_PID=""
+_PROXY_SERVER_PID=""
 
 # Start test MCP server
 # Usage: start_test_server [env_vars...]
@@ -665,6 +674,35 @@ EOF
   fi
 }
 
+# Start a local HTTP proxy server (proxy-chain) for testing HTTPS_PROXY / HTTP_PROXY support.
+# Sets PROXY_URL and PROXY_CONTROL_URL in the environment.
+start_proxy_server() {
+  local log="$_TEST_RUN_DIR/proxy-server.log"
+  cd "$PROJECT_ROOT"
+  npx tsx test/e2e/server/proxy-server.ts >"$log" 2>&1 &
+  _PROXY_SERVER_PID=$!
+
+  # Wait for PROXY_PORT= line in log (up to 10 seconds)
+  local max_wait=50
+  local waited=0
+  while ! grep -q "^PROXY_PORT=" "$log" 2>/dev/null; do
+    sleep 0.2
+    ((waited++)) || true
+    if [[ $waited -ge $max_wait ]]; then
+      echo "Error: Proxy server failed to start" >&2
+      cat "$log" >&2
+      kill $_PROXY_SERVER_PID 2>/dev/null || true
+      exit 1
+    fi
+  done
+
+  local proxy_port
+  proxy_port=$(grep "^PROXY_PORT=" "$log" | cut -d= -f2 | tr -d '[:space:]')
+
+  export PROXY_URL="http://127.0.0.1:${proxy_port}"
+  echo "# Proxy server started at $PROXY_URL (PID: $_PROXY_SERVER_PID)"
+}
+
 # Stop test server
 stop_test_server() {
   if [[ -n "$_TEST_SERVER_PID" ]]; then

test/e2e/server/index.ts

@@ -195,10 +195,10 @@ function shouldFail(): boolean {
   return false;
 }
 
-// MCP server instance (accessible for sending notifications)
-let mcpServer: Server | null = null;
+// Active MCP server instances, keyed by session ID
+const mcpServers = new Map<string, Server>();
 
-// Create the MCP server
+// Create a new MCP server instance (one per session)
 function createMcpServer(): Server {
   const server = new Server(
     {
@@ -387,7 +387,6 @@ function createMcpServer(): Server {
 
 // Create HTTP server with MCP transport and control endpoints
 async function main() {
-  mcpServer = createMcpServer();
   const transports = new Map<string, StreamableHTTPServerTransport>();
 
   const httpServer = http.createServer(async (req, res) => {
@@ -451,36 +450,21 @@ async function main() {
           return;
 
         case 'notify-tools-changed':
-          if (mcpServer) {
-            await mcpServer.sendToolListChanged();
-            res.writeHead(200);
-            res.end('Sent tools/list_changed notification');
-          } else {
-            res.writeHead(500);
-            res.end('MCP server not initialized');
-          }
+          await Promise.all([...mcpServers.values()].map((s) => s.sendToolListChanged()));
+          res.writeHead(200);
+          res.end('Sent tools/list_changed notification');
           return;
 
         case 'notify-prompts-changed':
-          if (mcpServer) {
-            await mcpServer.sendPromptListChanged();
-            res.writeHead(200);
-            res.end('Sent prompts/list_changed notification');
-          } else {
-            res.writeHead(500);
-            res.end('MCP server not initialized');
-          }
+          await Promise.all([...mcpServers.values()].map((s) => s.sendPromptListChanged()));
+          res.writeHead(200);
+          res.end('Sent prompts/list_changed notification');
           return;
 
         case 'notify-resources-changed':
-          if (mcpServer) {
-            await mcpServer.sendResourceListChanged();
-            res.writeHead(200);
-            res.end('Sent resources/list_changed notification');
-          } else {
-            res.writeHead(500);
-            res.end('MCP server not initialized');
-          }
+          await Promise.all([...mcpServers.values()].map((s) => s.sendResourceListChanged()));
+          res.writeHead(200);
+          res.end('Sent resources/list_changed notification');
           return;
 
         default:
@@ -518,6 +502,7 @@ async function main() {
           const oldTransport = transports.get(mcpSessionId)!;
           await oldTransport.close();
           transports.delete(mcpSessionId);
+          mcpServers.delete(mcpSessionId);
           deletedSessions.push(mcpSessionId);
         }
         res.writeHead(200);
@@ -530,19 +515,21 @@ async function main() {
       if (mcpSessionId && transports.has(mcpSessionId)) {
         transport = transports.get(mcpSessionId)!;
       } else if (req.method === 'POST' && !mcpSessionId) {
-        // New session - create transport
+        // New session - create a fresh Server + transport per connection
+        const sessionServer = createMcpServer();
         transport = new StreamableHTTPServerTransport({
           sessionIdGenerator: () =>
             `e2e-session-${Date.now()}-${Math.random().toString(36).slice(2)}`,
           onsessioninitialized: (newSessionId) => {
             transports.set(newSessionId, transport);
+            mcpServers.set(newSessionId, sessionServer);
           },
         });
 
-        // Connect to MCP server
+        // Connect the fresh server instance to the transport
         // Type assertion needed due to exactOptionalPropertyTypes incompatibility with MCP SDK
         // @ts-ignore
-        await mcpServer.connect(transport as Parameters<typeof mcpServer.connect>[0]);
+        await sessionServer.connect(transport as Parameters<typeof sessionServer.connect>[0]);
       } else if (mcpSessionId && !transports.has(mcpSessionId)) {
         // Session ID provided but not found - per MCP spec, return 404
         res.writeHead(404, { 'Content-Type': 'application/json' });

test/e2e/server/proxy-server.ts

@@ -0,0 +1,21 @@
+/**
+ * Simple HTTP proxy server for E2E testing
+ * Uses proxy-chain to forward requests.
+ *
+ * Outputs to stdout once ready:
+ *   PROXY_PORT=<port>
+ */
+
+import { Server } from 'proxy-chain';
+
+const proxyServer = new Server({ port: 0, verbose: false });
+
+await proxyServer.listen();
+
+// Signal readiness to the bash framework
+process.stdout.write(`PROXY_PORT=${proxyServer.port}\n`);
+
+process.on('SIGTERM', () => {
+  proxyServer.close();
+  process.exit(0);
+});