diff --git a/src/runtime/protocol.ts b/src/runtime/protocol.ts
index 91635ce..c822329 100644
--- a/src/runtime/protocol.ts
+++ b/src/runtime/protocol.ts
@@ -17,6 +17,7 @@ export function buildPayload(req: any, subPath: string): string {
 export function readVsockResponse(
   socket: Socket,
   timeout: number,
+  onStreamChunk?: (chunk: any) => void
 ): Promise<{ type: string; data: any; error?: string }> {
   return new Promise((resolve, reject) => {
     let buffer = "";
@@ -41,6 +42,14 @@ export function readVsockResponse(
     onData = (chunk: Buffer) => {
       buffer += chunk.toString();
 
+      if (buffer.length > 10 * 1024 * 1024) {
+        clearTimeout(timer);
+        cleanup();
+        socket.destroy();
+        reject(new Error("Response too large"));
+        return;
+      }
+
       let index;
 
       while ((index = buffer.indexOf("\n")) >= 0) {
@@ -53,6 +62,11 @@ export function readVsockResponse(
         try {
           const msg = JSON.parse(line);
 
+          if (msg.type === "stream") {
+            onStreamChunk?.(msg);
+            continue;
+          }
+
           if (msg.type === "response" || msg.type === "error") {
             clearTimeout(timer);
             cleanup();
diff --git a/src/runtime/transport.ts b/src/runtime/transport.ts
index f853189..e4a3c47 100644
--- a/src/runtime/transport.ts
+++ b/src/runtime/transport.ts
@@ -90,3 +90,20 @@ export async function sendRequest(subPath: string, req: any, res: any, vm: Vm) {
     res.status(statusCode).json(msg.data ?? { error: msg.error });
   }
 }
+
+export async function sendMessage(
+  vm: Vm,
+  message: Record<string, any>,
+  onStreamChunk?: (chunk: any) => void,
+  timeout: number = 60000,
+): Promise<any> {
+  const socket = await getVmSocket(vm);
+  socket.write(JSON.stringify(message) + "\n");
+
+  transportLogger.debug(
+    { vmId: vm.id, messageType: message.type, messageId: message.id },
+    "message sent to VM"
+  );
+
+  return readVsockResponse(socket, timeout, onStreamChunk);
+}
diff --git a/src/types/types.ts b/src/types/types.ts
index a5ce129..cdb539d 100644
--- a/src/types/types.ts
+++ b/src/types/types.ts
@@ -34,3 +34,59 @@ export interface RuntimeFunction {
   vms: Vm[];
   readyVms: Set<Vm>;
 }
+
+export interface ExecuteMessage {
+  type: "execute";
+  id: string;
+  command: string;
+  args: string[];
+  cwd?: string;
+  env?: Record<string, string>;
+  timeout?: number;
+}
+
+export interface WriteFileMessage {
+  type: "write_file";
+  id: string;
+  path: string;
+  content: string;
+  mode?: number;
+}
+
+export interface ReadFileMessage {
+  type: "read_file";
+  id: string;
+  path: string;
+}
+
+export interface ListFilesMessage {
+  type: "list_files";
+  id: string;
+  path?: string;
+  recursive?: boolean;
+}
+
+export interface CancelMessage {
+  type: "cancel";
+  id: string;
+}
+
+export interface StreamMessage {
+  type: "stream";
+  id: string;
+  stream: "stdout" | "stderr";
+  data: string;
+}
+
+export interface ResponseMessage {
+  type: "response";
+  id: string;
+  data: any;
+}
+
+export interface ErrorMessage {
+  type: "error";
+  id: string;
+  error: string;
+  code?: number;
+}