From 9f231af27036f5f8ea74a8cf0b99610ecf46993e Mon Sep 17 00:00:00 2001
From: Ultronen <82553854+Ultronen@users.noreply.github.com>
Date: Sun, 6 Sep 2026 18:22:18 +0800
Subject: [PATCH] refactor(proxy): keep guardrail projection immutable

---
 litellm/proxy/utils.py | 21 ++++++++-------------
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/litellm/proxy/utils.py b/litellm/proxy/utils.py
index e1ec9444a6e..9c9f643d626 100644
--- a/litellm/proxy/utils.py
+++ b/litellm/proxy/utils.py
@@ -907,23 +907,18 @@ def _streaming_guardrail_response_text(*, complete_response: str, response: obje
     if not isinstance(response, (ModelResponse, ModelResponseStream)):
         return complete_response
     response_dict: Final = response.model_dump(mode="json", exclude_none=True)
-    structured_choices: Final = tuple(
-        {key: delta[key] for key in ("tool_calls", "function_call") if delta.get(key) is not None}
-        for choice in response_dict.get("choices", [])
+    structured_fields: Final = tuple(
+        f"{key}:{json.dumps(delta[key], ensure_ascii=False, separators=(',', ':'), sort_keys=True)}"
+        for choice in response_dict.get("choices", ())
         if isinstance(choice, dict)
         for delta in (choice.get("delta"),)
-        if isinstance(delta, dict) and any(delta.get(key) is not None for key in ("tool_calls", "function_call"))
+        if isinstance(delta, dict)
+        for key in ("tool_calls", "function_call")
+        if delta.get(key) is not None
     )
-    if not structured_choices:
+    if not structured_fields:
         return complete_response
-    return _StreamingHookResponseText(
-        json.dumps(
-            {"content": str(complete_response), "choices": structured_choices},
-            ensure_ascii=False,
-            separators=(",", ":"),
-            sort_keys=True,
-        )
-    )
+    return _StreamingHookResponseText("\n".join((str(complete_response), *structured_fields)))
 
 
 def _is_unchanged_structured_streaming_hook_response(