From 04eb6062e4c22a471d0a733d5fad8ad517e7c0f2 Mon Sep 17 00:00:00 2001
From: Jon Durbin <jon@jondurbin.com>
Date: Thu, 27 Mar 2025 23:23:18 -0400
Subject: [PATCH] Include context length in /v1/models response. (#4809)

---
 python/sglang/srt/entrypoints/http_server.py | 8 +++++++-
 python/sglang/srt/openai_api/protocol.py     | 1 +
 test/srt/test_openai_server.py               | 6 ++++++
 3 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/python/sglang/srt/entrypoints/http_server.py b/python/sglang/srt/entrypoints/http_server.py
index 1024370a1..1f93b475c 100644
--- a/python/sglang/srt/entrypoints/http_server.py
+++ b/python/sglang/srt/entrypoints/http_server.py
@@ -561,7 +561,13 @@ def available_models():
     served_model_names = [_global_state.tokenizer_manager.served_model_name]
     model_cards = []
     for served_model_name in served_model_names:
-        model_cards.append(ModelCard(id=served_model_name, root=served_model_name))
+        model_cards.append(
+            ModelCard(
+                id=served_model_name,
+                root=served_model_name,
+                max_model_len=_global_state.tokenizer_manager.model_config.context_len,
+            )
+        )
     return ModelList(data=model_cards)
 
 
diff --git a/python/sglang/srt/openai_api/protocol.py b/python/sglang/srt/openai_api/protocol.py
index 60a01766d..751b8befe 100644
--- a/python/sglang/srt/openai_api/protocol.py
+++ b/python/sglang/srt/openai_api/protocol.py
@@ -28,6 +28,7 @@ class ModelCard(BaseModel):
     created: int = Field(default_factory=lambda: int(time.time()))
     owned_by: str = "sglang"
     root: Optional[str] = None
+    max_model_len: Optional[int] = None
 
 
 class ModelList(BaseModel):
diff --git a/test/srt/test_openai_server.py b/test/srt/test_openai_server.py
index af2ed20e9..fe6646d60 100644
--- a/test/srt/test_openai_server.py
+++ b/test/srt/test_openai_server.py
@@ -542,6 +542,12 @@ The SmartHome Mini is a compact smart home assistant available in black or white
             .startswith('"name": "SmartHome Mini",')
         )
 
+    def test_model_list(self):
+        client = openai.Client(api_key=self.api_key, base_url=self.base_url)
+        models = list(client.models.list())
+        assert len(models) == 1
+        assert isinstance(getattr(models[0], "max_model_len", None), int)
+
 
 # -------------------------------------------------------------------------
 #    EBNF Test Class: TestOpenAIServerEBNF