From 17377872332b334c58479c794823c9831be4f8f9 Mon Sep 17 00:00:00 2001
From: Sameer Kankute <sameer@berri.ai>
Date: Mon, 18 May 2026 14:29:10 +0530
Subject: [PATCH] fix(interactions): only set object/id/delta on step.stop for
 legacy schema
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StepStop (new schema) has no object, id, or delta fields. Setting them
unconditionally caused spec-breaking extra fields on new-schema step.stop
events in all four construction sites (sync/async × main-loop/StopIteration).

Legacy content.stop still receives id, object, and delta unchanged.

Co-authored-by: Cursor <cursoragent@cursor.com>
---
 .../streaming_iterator.py                            | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/litellm/interactions/litellm_responses_transformation/streaming_iterator.py b/litellm/interactions/litellm_responses_transformation/streaming_iterator.py
index 3627736fde9..9c18b511605 100644
--- a/litellm/interactions/litellm_responses_transformation/streaming_iterator.py
+++ b/litellm/interactions/litellm_responses_transformation/streaming_iterator.py
@@ -244,10 +244,10 @@ class LiteLLMResponsesInteractionsStreamingIterator:
                         stop_kwargs: Dict[str, Any] = {
                             "event_type": stop_event_type,
                             "index": 0,
-                            "id": transformed.id,
-                            "object": "content",
                         }
                         if self._use_legacy:
+                            stop_kwargs["id"] = transformed.id
+                            stop_kwargs["object"] = "content"
                             stop_kwargs["delta"] = {
                                 "type": "text",
                                 "text": self.collected_text,
@@ -270,9 +270,9 @@ class LiteLLMResponsesInteractionsStreamingIterator:
                     stop_kwargs = {
                         "event_type": stop_event_type,
                         "index": 0,
-                        "object": "content",
                     }
                     if self._use_legacy:
+                        stop_kwargs["object"] = "content"
                         stop_kwargs["delta"] = {
                             "type": "text",
                             "text": self.collected_text,
@@ -330,10 +330,10 @@ class LiteLLMResponsesInteractionsStreamingIterator:
                         stop_kwargs_async: Dict[str, Any] = {
                             "event_type": stop_event_type,
                             "index": 0,
-                            "id": transformed.id,
-                            "object": "content",
                         }
                         if self._use_legacy:
+                            stop_kwargs_async["id"] = transformed.id
+                            stop_kwargs_async["object"] = "content"
                             stop_kwargs_async["delta"] = {
                                 "type": "text",
                                 "text": self.collected_text,
@@ -358,9 +358,9 @@ class LiteLLMResponsesInteractionsStreamingIterator:
                     stop_kwargs_async = {
                         "event_type": stop_event_type,
                         "index": 0,
-                        "object": "content",
                     }
                     if self._use_legacy:
+                        stop_kwargs_async["object"] = "content"
                         stop_kwargs_async["delta"] = {
                             "type": "text",
                             "text": self.collected_text,