diff --git a/.changeset/stateless-json-response.md b/.changeset/stateless-json-response.md
new file mode 100644
index 00000000..352e9dc0
--- /dev/null
+++ b/.changeset/stateless-json-response.md
@@ -0,0 +1,5 @@
+---
+"@nuxtjs/mcp-toolkit": patch
+---
+
+fix(transport): use JSON response mode for stateless Node transport
\ No newline at end of file
diff --git a/packages/nuxt-mcp-toolkit/src/runtime/server/mcp/providers/node.ts b/packages/nuxt-mcp-toolkit/src/runtime/server/mcp/providers/node.ts
index 2effdc64..493a26d1 100644
--- a/packages/nuxt-mcp-toolkit/src/runtime/server/mcp/providers/node.ts
+++ b/packages/nuxt-mcp-toolkit/src/runtime/server/mcp/providers/node.ts
@@ -84,7 +84,16 @@ export default createMcpTransportHandler(async (createServer, event) => {
 
     const server = createServer()
     event.context._mcpServer = server
-    const transport = new WebStandardStreamableHTTPServerTransport({ sessionIdGenerator: undefined })
+    const transport = new WebStandardStreamableHTTPServerTransport({
+      sessionIdGenerator: undefined,
+      // In stateless mode, use JSON responses instead of SSE so that H3 can
+      // fully await the response and afterResponse fires only after the tool
+      // handler completes. With SSE the response stream is returned immediately
+      // (before the handler runs), which causes serverless runtimes to fire
+      // afterResponse too early and drops any log.set() calls made after async
+      // work inside the handler.
+      enableJsonResponse: true,
+    })
     onResponseClose(event, () => {
       transport.close()
       server.close()