From 9dacaf39576d1a7fbcaa0d9040d7a0c697a372bc Mon Sep 17 00:00:00 2001
From: Bao Nguyen <b@nqbao.com>
Date: Sun, 3 May 2026 23:09:59 -0700
Subject: [PATCH] fix(deepseek): allow thinking parameter to accept "disabled"
 type

---
 litellm/llms/deepseek/chat/transformation.py       | 14 +++++++-------
 .../chat/test_deepseek_chat_transformation.py      | 14 ++++++++++++++
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/litellm/llms/deepseek/chat/transformation.py b/litellm/llms/deepseek/chat/transformation.py
index 9cadecb196a..03f58659ca7 100644
--- a/litellm/llms/deepseek/chat/transformation.py
+++ b/litellm/llms/deepseek/chat/transformation.py
@@ -47,14 +47,14 @@ class DeepSeekChatConfig(OpenAIGPTConfig):
         thinking_value = optional_params.pop("thinking", None)
         reasoning_effort = optional_params.pop("reasoning_effort", None)
 
-        # Handle thinking parameter - only accept {"type": "enabled"}
+        # Handle thinking parameter - accept {"type": "enabled"} or {"type": "disabled"}
         if thinking_value is not None:
-            if (
-                isinstance(thinking_value, dict)
-                and thinking_value.get("type") == "enabled"
-            ):
-                # DeepSeek only accepts {"type": "enabled"}, ignore budget_tokens
-                optional_params["thinking"] = {"type": "enabled"}
+            if isinstance(thinking_value, dict) and thinking_value.get(
+                "type"
+            ) in ("enabled", "disabled"):
+                optional_params["thinking"] = {
+                    "type": thinking_value["type"]
+                }
 
         # Handle reasoning_effort - map to thinking enabled/disabled
         elif reasoning_effort is not None:
diff --git a/tests/litellm/llms/deepseek/chat/test_deepseek_chat_transformation.py b/tests/litellm/llms/deepseek/chat/test_deepseek_chat_transformation.py
index e6f2a9ad023..34aec2982f3 100644
--- a/tests/litellm/llms/deepseek/chat/test_deepseek_chat_transformation.py
+++ b/tests/litellm/llms/deepseek/chat/test_deepseek_chat_transformation.py
@@ -139,6 +139,20 @@ class TestDeepSeekThinkingParams:
         # thinking should be set, reasoning_effort should not override
         assert result["thinking"] == {"type": "enabled"}
 
+    def test_map_thinking_disabled(self):
+        """Test that thinking={"type": "disabled"} is passed through correctly."""
+        non_default_params = {"thinking": {"type": "disabled"}}
+        optional_params = {}
+
+        result = self.config.map_openai_params(
+            non_default_params=non_default_params,
+            optional_params=optional_params,
+            model=self.model,
+            drop_params=False,
+        )
+
+        assert result["thinking"] == {"type": "disabled"}
+
     def test_invalid_thinking_type_ignored(self):
         """Test that invalid thinking type values are ignored."""
         non_default_params = {"thinking": {"type": "invalid"}}