From 435ca7b16dfd451647c2034e3777066d54fe8a18 Mon Sep 17 00:00:00 2001
From: Laura Promberger <laura.promberger@amd.com>
Date: Mon, 2 Feb 2026 13:47:40 +0000
Subject: [PATCH] fix vscode plugin to not fail if another vscode host is
 already running the mcp server

---
 vscode-plugins/stella-ide-mcp/extension.js | 55 +++++++++++++++++++---
 1 file changed, 49 insertions(+), 6 deletions(-)

diff --git a/vscode-plugins/stella-ide-mcp/extension.js b/vscode-plugins/stella-ide-mcp/extension.js
index 747f603..f398337 100644
--- a/vscode-plugins/stella-ide-mcp/extension.js
+++ b/vscode-plugins/stella-ide-mcp/extension.js
@@ -249,6 +249,29 @@ async function handleCallTool(params) {
     }
 }
 
+// Check if server is already running on port
+function checkServerRunning(port) {
+    return new Promise((resolve) => {
+        const req = http.get(`http://127.0.0.1:${port}/health`, (res) => {
+            let data = '';
+            res.on('data', chunk => data += chunk);
+            res.on('end', () => {
+                try {
+                    const json = JSON.parse(data);
+                    resolve(json.status === 'ok' && json.tools === TOOLS.length);
+                } catch {
+                    resolve(false);
+                }
+            });
+        });
+        req.on('error', () => resolve(false));
+        req.setTimeout(1000, () => {
+            req.destroy();
+            resolve(false);
+        });
+    });
+}
+
 // HTTP Server
 function startServer(port) {
     server = http.createServer(async (req, res) => {
@@ -357,9 +380,21 @@ function startServer(port) {
         vscode.window.showInformationMessage(`Stella IDE MCP server running on port ${port}`);
     });
 
-    server.on('error', (e) => {
-        log(`Server error: ${e.message}`);
-        vscode.window.showErrorMessage(`Stella IDE MCP server error: ${e.message}`);
+    server.on('error', async (e) => {
+        if (e.code === 'EADDRINUSE') {
+            log(`Port ${port} in use, checking if it's another instance...`);
+            const isOurServer = await checkServerRunning(port);
+            if (isOurServer) {
+                log(`Server already running in another extension host on port ${port} - skipping`);
+                server = null; // Clear server reference since we're not running it
+            } else {
+                log(`Port ${port} occupied by another process`);
+                vscode.window.showErrorMessage(`Stella IDE MCP: Port ${port} is in use by another process`);
+            }
+        } else {
+            log(`Server error: ${e.message}`);
+            vscode.window.showErrorMessage(`Stella IDE MCP server error: ${e.message}`);
+        }
     });
 }
 
@@ -382,13 +417,21 @@ function activate(context) {
     startServer(port);
 
     // Status command
-    const statusCmd = vscode.commands.registerCommand('stella-ide-mcp.status', () => {
+    const statusCmd = vscode.commands.registerCommand('stella-ide-mcp.status', async () => {
         if (server && server.listening) {
             vscode.window.showInformationMessage(
-                `Stella IDE MCP server running on port ${port}. Tools: ${TOOLS.map(t => t.name).join(', ')}`
+                `Stella IDE MCP server running on port ${port} (this extension host). Tools: ${TOOLS.map(t => t.name).join(', ')}`
             );
         } else {
-            vscode.window.showWarningMessage('Stella IDE MCP server is not running');
+            // Check if server is running in another extension host
+            const isRunning = await checkServerRunning(port);
+            if (isRunning) {
+                vscode.window.showInformationMessage(
+                    `Stella IDE MCP server running on port ${port} (another extension host). Tools: ${TOOLS.map(t => t.name).join(', ')}`
+                );
+            } else {
+                vscode.window.showWarningMessage('Stella IDE MCP server is not running');
+            }
         }
     });