From 84aef37808040b05b86aa61b8308ebf7506e7199 Mon Sep 17 00:00:00 2001
From: Raghav Ravishankar <113712354+alyosha-swamy@users.noreply.github.com>
Date: Tue, 20 Jan 2026 08:03:17 +0530
Subject: [PATCH] fix function calling for Trinity (#17364)

---
 .../srt/function_call/function_call_parser.py |  2 +
 .../srt/function_call/trinity_detector.py     | 43 +++++++++++++++++++
 2 files changed, 45 insertions(+)
 create mode 100644 python/sglang/srt/function_call/trinity_detector.py

diff --git a/python/sglang/srt/function_call/function_call_parser.py b/python/sglang/srt/function_call/function_call_parser.py
index 8df0a2401..df03dae71 100644
--- a/python/sglang/srt/function_call/function_call_parser.py
+++ b/python/sglang/srt/function_call/function_call_parser.py
@@ -27,6 +27,7 @@ from sglang.srt.function_call.pythonic_detector import PythonicDetector
 from sglang.srt.function_call.qwen3_coder_detector import Qwen3CoderDetector
 from sglang.srt.function_call.qwen25_detector import Qwen25Detector
 from sglang.srt.function_call.step3_detector import Step3Detector
+from sglang.srt.function_call.trinity_detector import TrinityDetector
 from sglang.srt.function_call.utils import get_json_schema_constraint
 
 logger = logging.getLogger(__name__)
@@ -59,6 +60,7 @@ class FunctionCallParser:
         "qwen3_coder": Qwen3CoderDetector,
         "step3": Step3Detector,
         "minimax-m2": MinimaxM2Detector,
+        "trinity": TrinityDetector,
         "interns1": InternlmDetector,
     }
 
diff --git a/python/sglang/srt/function_call/trinity_detector.py b/python/sglang/srt/function_call/trinity_detector.py
new file mode 100644
index 000000000..e6288d3b3
--- /dev/null
+++ b/python/sglang/srt/function_call/trinity_detector.py
@@ -0,0 +1,43 @@
+import logging
+from typing import List
+
+from sglang.srt.entrypoints.openai.protocol import Tool
+from sglang.srt.function_call.core_types import StreamingParseResult
+from sglang.srt.function_call.qwen25_detector import Qwen25Detector
+
+logger = logging.getLogger(__name__)
+
+
+class TrinityDetector(Qwen25Detector):
+    """
+    Detector for Trinity models using Qwen-style function call format.
+
+    This detector extends Qwen25Detector to handle tool calls that may appear
+    inside <think> sections by stripping the think tags before parsing.
+
+    Reference: https://huggingface.co/Qwen/Qwen2.5-0.5B-Instruct?chat_template=default
+    """
+
+    def _strip_think_tags(self, text: str) -> str:
+        """Remove <think> and </think> tags, keeping the content inside."""
+        return text.replace("<think>", "").replace("</think>", "")
+
+    def has_tool_call(self, text: str) -> bool:
+        """Check if the text contains a tool call."""
+        return super().has_tool_call(self._strip_think_tags(text))
+
+    def detect_and_parse(self, text: str, tools: List[Tool]) -> StreamingParseResult:
+        """
+        One-time parsing: Detects and parses tool calls in the provided text.
+        """
+        return super().detect_and_parse(self._strip_think_tags(text), tools)
+
+    def parse_streaming_increment(
+        self, new_text: str, tools: List[Tool]
+    ) -> StreamingParseResult:
+        """
+        Streaming incremental parsing for tool calls.
+        """
+        return super().parse_streaming_increment(
+            self._strip_think_tags(new_text), tools
+        )