diff --git a/package-lock.json b/package-lock.json
new file mode 100644
index 0000000..1d9cdfd
--- /dev/null
+++ b/package-lock.json
@@ -0,0 +1,58 @@
+{
+  "name": "copilot-bridge",
+  "version": "0.1.0",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "name": "copilot-bridge",
+      "version": "0.1.0",
+      "devDependencies": {
+        "@types/node": "^20.10.0",
+        "@types/vscode": "^1.90.0",
+        "typescript": "^5.4.0"
+      },
+      "engines": {
+        "vscode": "^1.90.0"
+      }
+    },
+    "node_modules/@types/node": {
+      "version": "20.19.10",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-20.19.10.tgz",
+      "integrity": "sha512-iAFpG6DokED3roLSP0K+ybeDdIX6Bc0Vd3mLW5uDqThPWtNos3E+EqOM11mPQHKzfWHqEBuLjIlsBQQ8CsISmQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "undici-types": "~6.21.0"
+      }
+    },
+    "node_modules/@types/vscode": {
+      "version": "1.102.0",
+      "resolved": "https://registry.npmjs.org/@types/vscode/-/vscode-1.102.0.tgz",
+      "integrity": "sha512-V9sFXmcXz03FtYTSUsYsu5K0Q9wH9w9V25slddcxrh5JgORD14LpnOA7ov0L9ALi+6HrTjskLJ/tY5zeRF3TFA==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/typescript": {
+      "version": "5.9.2",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.9.2.tgz",
+      "integrity": "sha512-CWBzXQrc/qOkhidw1OzBTQuYRbfyxDXJMVJ1XNwUHGROVmuaeiEm3OslpZ1RV96d7SKKjZKrSJu3+t/xlw3R9A==",
+      "dev": true,
+      "license": "Apache-2.0",
+      "bin": {
+        "tsc": "bin/tsc",
+        "tsserver": "bin/tsserver"
+      },
+      "engines": {
+        "node": ">=14.17"
+      }
+    },
+    "node_modules/undici-types": {
+      "version": "6.21.0",
+      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-6.21.0.tgz",
+      "integrity": "sha512-iwDZqg0QAGrg9Rav5H4n0M64c3mkR59cJ6wQp+7C4nI0gsmExaedaYLNO44eT4AtBBwjbTiGPMlt2Md0T9H9JQ==",
+      "dev": true,
+      "license": "MIT"
+    }
+  }
+}
diff --git a/package.json b/package.json
index 0ef6304..03c59d6 100644
--- a/package.json
+++ b/package.json
@@ -73,7 +73,7 @@
   },
   "devDependencies": {
     "@types/node": "^20.10.0",
-    "typescript": "^5.4.0",
-    "vscode": "^1.1.40"
+    "@types/vscode": "^1.90.0",
+    "typescript": "^5.4.0"
   }
 }
diff --git a/src/extension.ts b/src/extension.ts
index 2e89183..5d54652 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -58,7 +58,7 @@ async function startBridge() {
       access = undefined;
     }
 
-    server = http.createServer(async (req, res) => {
+    server = http.createServer(async (req: http.IncomingMessage, res: http.ServerResponse) => {
       try {
         if (verbose) output?.appendLine(`HTTP ${req.method} ${req.url}`);
         if (token && req.headers.authorization !== `Bearer ${token}`) {
@@ -117,7 +117,7 @@ async function startBridge() {
               });
               const id = `cmp_${Math.random().toString(36).slice(2)}`;
               if (verbose) output?.appendLine(`SSE start id=${id}`);
-              const h1 = chatStream.onDidProduceContent((chunk) => {
+              const h1 = chatStream.onDidProduceContent((chunk: string) => {
                 const payload = {
                   id,
                   object: 'chat.completion.chunk',
@@ -137,7 +137,7 @@ async function startBridge() {
               return;
             } else {
               let buf = '';
-              const h1 = chatStream.onDidProduceContent((chunk) => { buf += chunk; });
+              const h1 = chatStream.onDidProduceContent((chunk: string) => { buf += chunk; });
               await new Promise<void>((resolve) => {
                 const h2 = chatStream.onDidEnd(() => {
                   h1.dispose();
@@ -220,7 +220,7 @@ function normalizeMessages(messages: any[], histWindow: number): string {
 function readJson(req: http.IncomingMessage): Promise<any> {
   return new Promise((resolve, reject) => {
     let data = '';
-    req.on('data', (c) => { data += c; });
+    req.on('data', (c: Buffer) => { data += c.toString(); });
     req.on('end', () => {
       if (!data) return resolve({});
       try { resolve(JSON.parse(data)); } catch (e) { reject(e); }
diff --git a/src/vscode-chat-shim.d.ts b/src/vscode-chat-shim.d.ts
new file mode 100644
index 0000000..2032ba1
--- /dev/null
+++ b/src/vscode-chat-shim.d.ts
@@ -0,0 +1,18 @@
+declare module 'vscode' {
+  namespace chat {
+    function requestChatAccess(providerId: string): Promise<ChatAccess>;
+  }
+
+  interface ChatAccess {
+    startSession(): Promise<ChatSession>;
+  }
+
+  interface ChatSession {
+    sendRequest(options: { prompt: string; attachments: any[] }): Promise<ChatResponseStream>;
+  }
+
+  interface ChatResponseStream {
+    onDidProduceContent(handler: (chunk: string) => void): { dispose(): void };
+    onDidEnd(handler: () => void): { dispose(): void };
+  }
+}