[eric] agents: hidden harness messages self-identify, so a misfired nudge can never become 'the user told me to stop' (field report)

backend/apps/agents/manager/Messaging.py

@@ -114,6 +114,12 @@ class Messaging(AgentManagerProtocol):
                 "session": session.model_dump(mode="json"),
             })
 
+        # Hidden messages are harness plumbing (nudges, lost-step retries, auth heals) but ride the
+        # USER role, so agents stopped mid-task by a misfired nudge truthfully reported "the user
+        # told me to stop", and others read them as prompt injection (field reports, 2026-08-16).
+        # One attribution prefix at the one send chokepoint keeps every explanation honest.
+        if hidden and prompt and not prompt.startswith("[Automated"):
+            prompt = "[Automated message from OpenSwarm itself, not written by your user] " + prompt
         skill_meta = [{"id": s["id"], "name": s["name"]} for s in (attached_skills or [])] or None
         image_meta = [{"data": img["data"], "media_type": img.get("media_type", "image/png")} for img in (images or [])] or None
         user_msg = Message(