diff --git a/server/src/index.ts b/server/src/index.ts
index ed79ae9..4bc7837 100644
--- a/server/src/index.ts
+++ b/server/src/index.ts
@@ -22,7 +22,7 @@ import mcpProxy from "./mcpProxy.js";
 import { randomUUID } from "node:crypto";
 
 const SSE_HEADERS_PASSTHROUGH = ["authorization"];
-const STREAMABLE_HTTP_HEADERS_PASSTHROUGH = ["authorization", "mcp-session-id"];
+const STREAMABLE_HTTP_HEADERS_PASSTHROUGH = ["authorization", "mcp-session-id", "last-event-id"];
 
 const defaultEnvironment = {
   ...getDefaultEnvironment(),