diff --git a/packages/agent/src/server/event-stream-sender.test.ts b/packages/agent/src/server/event-stream-sender.test.ts
index f351fa0cc7..c57825d318 100644
--- a/packages/agent/src/server/event-stream-sender.test.ts
+++ b/packages/agent/src/server/event-stream-sender.test.ts
@@ -208,49 +208,89 @@ describe("TaskRunEventStreamSender", () => {
     expect(lastCall[0]).not.toContain("/api/projects/");
   });
 
-  it("closes the active ingest upload after each drained batch on the proxy path", async () => {
+  it("keeps the active ingest request open across scheduled flushes", async () => {
     const requestBodies: string[] = [];
-    let contentUploads = 0;
+    let activeStreamClosed = false;
     const fetchMock = vi.fn(
       async (_url: string | URL | Request, init?: RequestInit) => {
         if (!init?.body || typeof init.body === "string") {
-          return responseForBody(await readRequestBody(init));
+          const body = await readRequestBody(init);
+          requestBodies.push(body);
+          return responseForBody(body);
         }
 
-        // Resolves only once the sender closes the upload body.
         const body = await readRequestBody(init);
-        contentUploads += 1;
+        activeStreamClosed = true;
         requestBodies.push(body);
         return responseForBody(body);
       },
     );
     vi.stubGlobal("fetch", fetchMock);
 
-    const sender = createSender({
-      flushDelayMs: 0,
-      eventIngestBaseUrl: "http://agent-proxy:8003/",
-    });
+    const sender = createSender({ flushDelayMs: 0 });
 
-    // A buffering ingress only forwards the request body when the upload
-    // closes, so each drained batch must ride its own promptly-closed upload
-    // rather than one long-lived request held open until stop.
     sender.enqueue({ type: "notification", notification: { method: "first" } });
-    await waitFor(() => contentUploads === 1);
-    expect(eventSequences(requestBodies[0])).toEqual([1]);
-    expect(completionSequences(requestBodies[0])).toEqual([]);
+    await waitFor(() => fetchMock.mock.calls.length === 2);
+    expect(activeStreamClosed).toBe(false);
 
     sender.enqueue({
       type: "notification",
       notification: { method: "second" },
     });
-    await waitFor(() => contentUploads === 2);
-    expect(eventSequences(requestBodies[1])).toEqual([2]);
-    expect(completionSequences(requestBodies[1])).toEqual([]);
+    await new Promise((resolve) => setTimeout(resolve, 0));
+    await new Promise((resolve) => setTimeout(resolve, 0));
+
+    expect(fetchMock).toHaveBeenCalledTimes(2);
+    expect(activeStreamClosed).toBe(false);
 
     await sender.stop();
 
-    const finalBody = requestBodies.at(-1) ?? "";
-    expect(completionSequences(finalBody)).toEqual([2]);
+    expect(fetchMock).toHaveBeenCalledTimes(2);
+    expect(activeStreamClosed).toBe(true);
+    expect(parseLines(requestBodies[1])).toEqual([
+      {
+        seq: 1,
+        event: { type: "notification", notification: { method: "first" } },
+      },
+      {
+        seq: 2,
+        event: { type: "notification", notification: { method: "second" } },
+      },
+      { type: STREAM_COMPLETE_CONTROL_TYPE, final_seq: 2 },
+    ]);
+  });
+
+  it("closes an idle active ingest request after the stream window elapses", async () => {
+    const requestBodies: string[] = [];
+    let activeStreamClosed = false;
+    const fetchMock = vi.fn(
+      async (_url: string | URL | Request, init?: RequestInit) => {
+        if (!init?.body || typeof init.body === "string") {
+          return responseForBody(await readRequestBody(init));
+        }
+
+        const body = await readRequestBody(init);
+        activeStreamClosed = true;
+        requestBodies.push(body);
+        return responseForBody(body);
+      },
+    );
+    vi.stubGlobal("fetch", fetchMock);
+
+    const sender = createSender({ flushDelayMs: 0, streamWindowMs: 5 });
+
+    sender.enqueue({ type: "notification", notification: { method: "first" } });
+    await waitFor(() => fetchMock.mock.calls.length === 2);
+    expect(activeStreamClosed).toBe(false);
+
+    await waitFor(() => activeStreamClosed, 200);
+    expect(eventSequences(requestBodies[0])).toEqual([1]);
+    expect(completionSequences(requestBodies[0])).toEqual([]);
+
+    await sender.stop();
+
+    expect(eventSequences(requestBodies[1])).toEqual([]);
+    expect(completionSequences(requestBodies[1])).toEqual([1]);
   });
 
   it("aborts a stuck ingest response after closing the request body", async () => {
diff --git a/packages/agent/src/server/event-stream-sender.ts b/packages/agent/src/server/event-stream-sender.ts
index 437cb5e98c..5e254ded40 100644
--- a/packages/agent/src/server/event-stream-sender.ts
+++ b/packages/agent/src/server/event-stream-sender.ts
@@ -69,7 +69,6 @@ export class TaskRunEventStreamSender {
   private readonly requestTimeoutMs: number;
   private readonly stopTimeoutMs: number;
   private readonly streamWindowMs: number;
-  private readonly usingProxy: boolean;
   private readonly createStreamingUpload: StreamingUploadFactory;
   private readonly encoder = new TextEncoder();
   private sequence = 0;
@@ -113,7 +112,6 @@ export class TaskRunEventStreamSender {
       config.requestTimeoutMs ?? DEFAULT_REQUEST_TIMEOUT_MS;
     this.stopTimeoutMs = config.stopTimeoutMs ?? DEFAULT_STOP_TIMEOUT_MS;
     this.streamWindowMs = config.streamWindowMs ?? DEFAULT_STREAM_WINDOW_MS;
-    this.usingProxy = usingProxy;
     this.createStreamingUpload =
       config.createStreamingUpload ?? createNodeStreamingUpload;
   }
@@ -210,16 +208,6 @@ export class TaskRunEventStreamSender {
 
     try {
       await flushPromise;
-      // On the proxy path, deliver the drained batch now instead of holding one
-      // long-lived upload. The ingress in front of the proxy buffers the ingest
-      // request body and only forwards it once the request closes, so a
-      // long-lived upload strands events; closing per batch forwards each within
-      // a round-trip. Gated to the proxy write leg so the Django path keeps its
-      // existing long-lived upload. The stop path leaves closing to drainForStop
-      // so the completion line rides the final upload.
-      if (!this.stopped && this.usingProxy) {
-        await this.closeActiveStream();
-      }
       return this.bufferedEvents.length < previousBufferLength;
     } catch (error) {
       this.config.logger.warn(