diff --git a/backend/open_webui/utils/middleware.py b/backend/open_webui/utils/middleware.py
index 9e749ac35..a2fd61bbb 100644
--- a/backend/open_webui/utils/middleware.py
+++ b/backend/open_webui/utils/middleware.py
@@ -827,10 +827,15 @@ def apply_source_context_to_messages(
     messages: list,
     sources: list,
     user_message: str,
+    include_content: bool = True,
 ) -> list:
     """
     Build source context from citation sources and apply to messages.
     Uses RAG template to format context for model consumption.
+
+    When include_content is False, emit <source> tags with id/name but no
+    document body — useful when the content is already present elsewhere
+    (e.g. in a tool result message) and only citation markers are needed.
     """
     if not sources or not user_message:
         return messages
@@ -844,10 +849,11 @@ def apply_source_context_to_messages(
             if src_id not in citation_idx:
                 citation_idx[src_id] = len(citation_idx) + 1
             src_name = source.get("source", {}).get("name")
+            body = doc if include_content else ""
             context_string += (
                 f'<source id="{citation_idx[src_id]}"'
                 + (f' name="{src_name}"' if src_name else "")
-                + f">{doc}</source>\n"
+                + f">{body}</source>\n"
             )
 
     context_string = context_string.strip()
@@ -4227,6 +4233,8 @@ async def streaming_chat_response_handler(response, ctx):
                         await event_emitter({"type": "source", "data": source})
 
                     # Apply source context to messages for model
+                    # Use metadata_only=True to avoid duplicating content
+                    # that is already in the tool result message.
                     all_tool_call_sources.extend(tool_call_sources)
                     if all_tool_call_sources and user_message:
                         # Restore original user message before re-applying to avoid recursive nesting
@@ -4238,6 +4246,7 @@ async def streaming_chat_response_handler(response, ctx):
                             form_data["messages"],
                             all_tool_call_sources,
                             user_message,
+                            include_content=False,
                         )
                     tool_call_sources.clear()