Feature/function calling update (#2700)

Co-authored-by: Mingyuan Ma <mamingyuan2001@berkeley.edu>
Co-authored-by: Chayenne <zhaochen20@outlook.com>
Co-authored-by: shuaills <shishuaiuoe@gmail.com>

python/sglang/srt/server_args.py

@@ -161,6 +161,7 @@ class ServerArgs:
 
     # Custom logit processor
     enable_custom_logit_processor: bool = False
+    tool_call_parser: str = None
 
     def __post_init__(self):
         # Set missing default values
@@ -877,6 +878,14 @@ class ServerArgs:
             action="store_true",
             help="Enable users to pass custom logit processors to the server (disabled by default for security)",
         )
+        # Function Calling
+        parser.add_argument(
+            "--tool-call-parser",
+            type=str,
+            choices=["qwen25", "mistral", "llama3"],
+            default=ServerArgs.tool_call_parser,
+            help="Specify the parser for handling tool-call interactions. Options include: 'qwen25', 'mistral', and 'llama3'.",
+        )
 
     @classmethod
     def from_cli_args(cls, args: argparse.Namespace):