fix(databricks): translate reasoning_effort to thinking for Gemini 2.5

litellm/llms/base_llm/chat/transformation.py

@@ -14,7 +14,6 @@
     Tuple,
     Type,
     Union,
-    cast,
 )
 
 import httpx
@@ -124,7 +123,15 @@ def update_optional_params_with_thinking_tokens(self, non_default_params: dict,
         if is_thinking_enabled and (
             "max_tokens" not in non_default_params and "max_completion_tokens" not in non_default_params
         ):
-            thinking_token_budget = cast(dict, optional_params["thinking"]).get("budget_tokens", None)
+            # `is_thinking_enabled` is True when `reasoning_effort` is set OR
+            # when `thinking` is set. Providers that pass `reasoning_effort`
+            # through natively (e.g. Databricks-Gemini-3+, Databricks-GPT-5)
+            # never populate an Anthropic-style `thinking` block, so guard
+            # against that case here.
+            thinking = optional_params.get("thinking")
+            if not isinstance(thinking, dict):
+                return
+            thinking_token_budget = thinking.get("budget_tokens", None)
             if thinking_token_budget is not None:
                 optional_params["max_tokens"] = thinking_token_budget + DEFAULT_MAX_TOKENS
 

litellm/llms/databricks/chat/transformation.py

@@ -268,6 +268,24 @@ def get_supported_openai_params(self, model: Optional[str] = None) -> list:
             "thinking",
         ]
 
+    @staticmethod
+    def _databricks_model_uses_anthropic_thinking_param(model: str) -> bool:
+        """
+        Per Databricks docs, Claude and Gemini 2.5 endpoints accept the
+        Anthropic-style `thinking={"type":"enabled","budget_tokens":N}` payload
+        and do NOT accept OpenAI's top-level `reasoning_effort`. Gemini 3+ and
+        GPT-5/GPT-OSS accept `reasoning_effort` natively and need no
+        translation.
+        """
+        from litellm.utils import _supports_factory
+
+        normalized = model.lower().replace(".", "-")
+        return _supports_factory(
+            model=normalized,
+            custom_llm_provider="databricks",
+            key="supports_anthropic_thinking_payload",
+        )
+
     def convert_anthropic_tool_to_databricks_tool(
         self, tool: Optional[AllAnthropicToolsValues]
     ) -> Optional[DatabricksTool]:
@@ -371,20 +389,22 @@ def map_openai_params(
                 "response_format", None
             )  # unsupported for claude models - if json_schema -> convert to tool call
 
-        if "reasoning_effort" in non_default_params and "claude" in model:
+        if "reasoning_effort" in non_default_params and self._databricks_model_uses_anthropic_thinking_param(model):
             reasoning_effort_value = non_default_params.get("reasoning_effort")
             mapped_thinking = AnthropicConfig._map_reasoning_effort(
                 reasoning_effort=reasoning_effort_value,
                 model=model,
                 custom_llm_provider="databricks",
                 llm_provider="databricks",
             )
+            is_claude = "claude" in model.lower()
             if mapped_thinking is None:
                 optional_params.pop("thinking", None)
                 optional_params.pop("output_config", None)
             else:
                 optional_params["thinking"] = mapped_thinking
-                if AnthropicConfig._is_adaptive_thinking_model(model, "databricks"):
+                # output_config + adaptive thinking is an Anthropic-only feature.
+                if is_claude and AnthropicConfig._is_adaptive_thinking_model(model, "databricks"):
                     mapped_effort: Optional[str] = None
                     if isinstance(reasoning_effort_value, str):
                         mapped_effort = REASONING_EFFORT_TO_OUTPUT_CONFIG_EFFORT.get(reasoning_effort_value)

litellm/model_prices_and_context_window_backup.json

@@ -13339,6 +13339,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-claude-haiku-4-5": {
@@ -13358,6 +13359,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-claude-opus-4": {
@@ -13377,6 +13379,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-claude-opus-4-1": {
@@ -13396,6 +13399,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-claude-opus-4-5": {
@@ -13415,6 +13419,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true,
         "supports_output_config": true
     },
@@ -13435,6 +13440,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-claude-sonnet-4-1": {
@@ -13454,6 +13460,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-claude-sonnet-4-5": {
@@ -13473,6 +13480,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-gemini-2-5-flash": {
@@ -13490,6 +13498,7 @@
         "output_dbu_cost_per_token": 3.5714e-05,
         "source": "https://www.databricks.com/product/pricing/proprietary-foundation-model-serving",
         "supports_function_calling": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-gemini-2-5-pro": {
@@ -13507,6 +13516,7 @@
         "output_dbu_cost_per_token": 0.000142857,
         "source": "https://www.databricks.com/product/pricing/proprietary-foundation-model-serving",
         "supports_function_calling": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-gemma-3-12b": {

litellm/types/utils.py

@@ -152,6 +152,7 @@ class ProviderSpecificModelInfo(TypedDict, total=False):
     supports_max_reasoning_effort: Optional[bool]
     supports_output_config: Optional[bool]
     supports_image_size: Optional[bool]
+    supports_anthropic_thinking_payload: Optional[bool]
     bedrock_output_config_effort_ceiling: Optional[Literal["low", "medium", "high", "max", "xhigh"]]
     bedrock_converse_supports_strict_tools: Optional[bool]
 

litellm/utils.py

@@ -5513,6 +5513,7 @@ def _get_model_info_helper(
                 supports_reasoning=_model_info.get("supports_reasoning", None),
                 supports_adaptive_thinking=_model_info.get("supports_adaptive_thinking", None),
                 supports_mid_conversation_system=_model_info.get("supports_mid_conversation_system", None),
+                supports_anthropic_thinking_payload=_model_info.get("supports_anthropic_thinking_payload", None),
                 supports_none_reasoning_effort=_model_info.get("supports_none_reasoning_effort", None),
                 supports_minimal_reasoning_effort=_model_info.get("supports_minimal_reasoning_effort", None),
                 supports_low_reasoning_effort=_model_info.get("supports_low_reasoning_effort", None),

model_prices_and_context_window.json

@@ -13339,6 +13339,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-claude-haiku-4-5": {
@@ -13358,6 +13359,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-claude-opus-4": {
@@ -13377,6 +13379,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-claude-opus-4-1": {
@@ -13396,6 +13399,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-claude-opus-4-5": {
@@ -13415,6 +13419,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true,
         "supports_output_config": true
     },
@@ -13435,6 +13440,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-claude-sonnet-4-1": {
@@ -13454,6 +13460,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-claude-sonnet-4-5": {
@@ -13473,6 +13480,7 @@
         "supports_assistant_prefill": true,
         "supports_function_calling": true,
         "supports_reasoning": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-gemini-2-5-flash": {
@@ -13490,6 +13498,7 @@
         "output_dbu_cost_per_token": 3.5714e-05,
         "source": "https://www.databricks.com/product/pricing/proprietary-foundation-model-serving",
         "supports_function_calling": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-gemini-2-5-pro": {
@@ -13507,6 +13516,7 @@
         "output_dbu_cost_per_token": 0.000142857,
         "source": "https://www.databricks.com/product/pricing/proprietary-foundation-model-serving",
         "supports_function_calling": true,
+        "supports_anthropic_thinking_payload": true,
         "supports_tool_choice": true
     },
     "databricks/databricks-gemma-3-12b": {