[Frontend] Generate valid tool call IDs when using tokenizer-mode=mistral (#12332)

vllm/transformers_utils/tokenizers/__init__.py

@@ -1,5 +1,8 @@
 # SPDX-License-Identifier: Apache-2.0
 
-from .mistral import MistralTokenizer, maybe_serialize_tool_calls
+from .mistral import (MistralTokenizer, maybe_serialize_tool_calls,
+                      truncate_tool_call_ids)
 
-__all__ = ["MistralTokenizer", "maybe_serialize_tool_calls"]
+__all__ = [
+    "MistralTokenizer", "maybe_serialize_tool_calls", "truncate_tool_call_ids"
+]

vllm/transformers_utils/tokenizers/mistral.py

@@ -68,6 +68,36 @@ def maybe_serialize_tool_calls(request: "ChatCompletionRequest"):
             request.messages[i]["tool_calls"] = validated_tool_calls
 
 
+def truncate_tool_call_ids(request: "ChatCompletionRequest"):
+    """Truncates tool call IDs for Mistral's ID requirements."""
+    for i, message in enumerate(request.messages):
+        if message.get("role") == 'assistant':
+            tool_calls = message.get("tool_calls", [])
+            for tool_call in tool_calls:
+                if len(tool_call["id"]) > 9:
+                    logger.warning(
+                        "Truncating tool call ID: %s to %s",
+                        tool_call["id"],
+                        tool_call["id"][-9:],
+                    )
+                    tool_call["id"] = tool_call["id"][-9:]
+
+            request.messages[i]["tool_calls"] = tool_calls
+
+        elif message.get("role") in {"tool_results", "tool"}:
+            if "tool_call_id" in message:
+                tool_call_id = message["tool_call_id"]
+
+                if len(tool_call_id) > 9:
+                    logger.warning(
+                        "Truncating tool_call_id: %s to %s",
+                        tool_call_id,
+                        tool_call_id[-9:],
+                    )
+                    tool_call_id = tool_call_id[-9:]
+                request.messages[i]["tool_call_id"] = tool_call_id
+
+
 def list_local_repo_files(repo_id: str, revision: Optional[str]) -> List[str]:
     repo_cache = os.path.join(
         huggingface_hub.constants.HF_HUB_CACHE,