fix(complexity_router): count structured tool results in context escalation

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

litellm/router_strategy/complexity_router/complexity_router.py

@@ -460,8 +460,22 @@ def _message_text(content: object) -> str:
     return content if isinstance(content, str) else ""
 
 
+def _estimated_content_characters(content: object) -> int:
+    if isinstance(content, str):
+        return len(content)
+    if isinstance(content, list):
+        return sum(_estimated_content_characters(part) for part in content)
+    if isinstance(content, Mapping):
+        content_type: Final = content.get("type")
+        if content_type == "text":
+            return _estimated_content_characters(content.get("text"))
+        if content_type == "tool_result":
+            return _estimated_content_characters(content.get("content"))
+    return 0
+
+
 def _estimated_conversation_tokens(messages: Sequence[Mapping[str, object]] | None) -> int:
-    return sum(len(_message_text(message.get("content"))) // 4 for message in messages or ())
+    return sum(_estimated_content_characters(message.get("content")) // 4 for message in messages or ())
 
 
 def _reminder_block_spans(lowered: str, open_marker: str, close_marker: str) -> Iterator[tuple[int, int]]:

tests/test_litellm/router_strategy/test_complexity_router.py

@@ -13538,9 +13538,13 @@ class TestHeuristicFirst:
                 ],
                 4,
             ),
+            (
+                [{"role": "user", "content": [{"type": "tool_result", "content": "abcdefghijklmnop"}]}],
+                4,
+            ),
         ],
     )
-    def test_estimated_conversation_tokens_counts_text_parts(self, messages, expected):
+    def test_estimated_conversation_tokens_counts_text_and_tool_result_parts(self, messages, expected):
         assert _estimated_conversation_tokens(messages) == expected
 
     @pytest.mark.asyncio

ui/litellm-dashboard/src/components/add_model/ClassificationMethodConfig.tsx

@@ -278,7 +278,9 @@ const ClassificationMethodConfig: React.FC<ClassificationMethodConfigProps> = ({
     const parsed: number = Number(raw);
     if (Number.isFinite(parsed)) {
       onChange({ ...value, heuristic_first_max_context_tokens: Math.max(1, Math.round(parsed)) });
+      return;
     }
+    onChange({ ...value, heuristic_first_max_context_tokens: undefined });
   };
 
   const handleHybridBoundaryMarginChange = (raw: string) => {