fix(bedrock): route gpt-6-astra reasoning_effort to reasoning.effort and mark Nova 2 tool_choice

The converse reasoning gate only matched openai.gpt-5, so gpt-6-astra fell through to
Anthropic's thinking block and Bedrock rejected the call with 400 Unknown parameter:
'thinking'. Match any openai.gpt-<digit> model at the three gate sites instead.

Nova 2 lite and pro accept forced tool_choice on Converse (verified live on
us.amazon.nova-2-lite-v1:0), so the nine Nova 2 registry keys now advertise
supports_tool_choice. The invoke dispatcher also forwards json_mode to Nova like it
already does for Anthropic and TwelveLabs.

litellm/llms/bedrock/chat/converse_transformation.py

@@ -4,6 +4,7 @@ Translating between OpenAI's `/chat/completion` format and Amazon's `/converse`
 
 import copy
 import json
+import re
 import time
 import types
 from collections.abc import Mapping
@@ -293,6 +294,10 @@ class AmazonConverseConfig(BaseConfig):
                     llm_provider="bedrock",
                 )
 
+    @staticmethod
+    def _is_openai_gpt_reasoning_model(model: str) -> bool:
+        return re.search(r"openai\.gpt-\d", model) is not None
+
     def _is_nova_2_model(self, model: str) -> bool:
         """
         Check if the model is a Nova 2 model that supports reasoningConfig.
@@ -423,14 +428,14 @@ class AmazonConverseConfig(BaseConfig):
         Handle the reasoning_effort parameter based on the model type.
 
         - GPT-OSS models: passed through unchanged via additionalModelRequestFields.
-        - OpenAI GPT-5.x models: mapped to ``reasoning.effort`` via additionalModelRequestFields.
+        - OpenAI GPT-5.x and GPT-6 models: mapped to ``reasoning.effort`` via additionalModelRequestFields.
         - Nova 2 models: transformed to reasoningConfig.
         - Anthropic models: mapped to ``thinking`` (and ``output_config.effort`` on
           adaptive Claude 4.6 / 4.7).
         """
         if "gpt-oss" in model:
             optional_params["reasoning_effort"] = reasoning_effort
-        elif "openai.gpt-5" in model:
+        elif self._is_openai_gpt_reasoning_model(model):
             reasoning: Final[BedrockConverseGptReasoningEffortBlock] = {"effort": reasoning_effort}
             optional_params["reasoning"] = reasoning
         elif self._is_nova_2_model(model):
@@ -564,7 +569,11 @@ class AmazonConverseConfig(BaseConfig):
             # only anthropic and mistral support tool choice config. otherwise (E.g. cohere) will fail the call - https://docs.aws.amazon.com/bedrock/latest/APIReference/API_runtime_ToolChoice.html
             supported_params.append("tool_choice")
 
-        if "gpt-oss" in model or "openai.gpt-5" in model or "openai.gpt-5" in base_model:
+        if (
+            "gpt-oss" in model
+            or self._is_openai_gpt_reasoning_model(model)
+            or self._is_openai_gpt_reasoning_model(base_model)
+        ):
             supported_params.append("reasoning_effort")
         elif self._is_nova_2_model(model):
             # Nova 2 models support reasoning_effort (transformed to reasoningConfig)
@@ -920,7 +929,7 @@ class AmazonConverseConfig(BaseConfig):
                 optional_params["_parallel_tool_use_config"] = {
                     "tool_choice": {"type": "auto", "disable_parallel_tool_use": not value}
                 }
-            if param == "thinking" and "openai.gpt-5" not in model:
+            if param == "thinking" and not self._is_openai_gpt_reasoning_model(model):
                 if (
                     isinstance(value, dict)
                     and value.get("type") == "adaptive"

litellm/llms/bedrock/chat/invoke_transformations/base_invoke_transformation.py

@@ -340,6 +340,7 @@ class AmazonInvokeConfig(BaseConfig, BaseAWSLLM):
                     optional_params=optional_params,
                     litellm_params=litellm_params,
                     encoding=encoding,
+                    json_mode=json_mode,
                 )
             elif provider == "twelvelabs":
                 return litellm.AmazonTwelveLabsPegasusConfig().transform_response(

litellm/model_prices_and_context_window_backup.json

@@ -381,6 +381,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -400,6 +401,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -417,6 +419,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -436,6 +439,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -453,6 +457,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -472,6 +477,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -489,6 +495,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -508,6 +515,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -28578,6 +28586,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },

model_prices_and_context_window.json

@@ -381,6 +381,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -400,6 +401,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -417,6 +419,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -436,6 +439,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -453,6 +457,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -472,6 +477,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -489,6 +495,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -508,6 +515,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },
@@ -28578,6 +28586,7 @@
         "supports_prompt_caching": true,
         "supports_reasoning": true,
         "supports_response_schema": true,
+        "supports_tool_choice": true,
         "supports_video_input": true,
         "supports_vision": true
     },

tests/test_litellm/llms/bedrock/chat/invoke_transformations/test_base_invoke_transformation.py

@@ -1,5 +1,7 @@
 import json
+from unittest.mock import MagicMock
 
+import httpx
 import pytest
 
 
@@ -190,3 +192,45 @@ def test_get_error_class_preserves_provider_headers():
     assert isinstance(error, BedrockError)
     assert error.headers == {"x-amzn-RequestId": "req-invoke-500"}
     assert error.response.headers["x-amzn-requestid"] == "req-invoke-500"
+
+
+def test_transform_response_hands_json_mode_to_nova():
+    """The invoke dispatcher forwards its json_mode argument to Nova instead of dropping it."""
+    from litellm.types.utils import ModelResponse
+
+    response_json = {
+        "output": {
+            "message": {
+                "role": "assistant",
+                "content": [
+                    {
+                        "toolUse": {
+                            "toolUseId": "tooluse_nova_json",
+                            "name": "json_tool_call",
+                            "input": {"city": "Paris", "temperature": 21},
+                        }
+                    }
+                ],
+            }
+        },
+        "stopReason": "tool_use",
+        "usage": {"inputTokens": 5, "outputTokens": 4, "totalTokens": 9},
+    }
+    raw_response = httpx.Response(200, json=response_json, request=httpx.Request("POST", "https://bedrock"))
+
+    result = AmazonInvokeConfig().transform_response(
+        model="invoke/amazon.nova-lite-v1:0",
+        raw_response=raw_response,
+        model_response=ModelResponse(),
+        logging_obj=MagicMock(),
+        request_data={},
+        messages=[{"role": "user", "content": "weather"}],
+        optional_params={},
+        litellm_params={},
+        encoding=None,
+        api_key=None,
+        json_mode=True,
+    )
+
+    assert result.choices[0].message.tool_calls is None
+    assert json.loads(result.choices[0].message.content) == {"city": "Paris", "temperature": 21}

tests/test_litellm/llms/bedrock/chat/test_converse_transformation.py

@@ -382,6 +382,8 @@ def test_reasoning_with_forced_tool_choice_switches_to_auto():
         "us.openai.gpt-5.6-sol",
         "global.openai.gpt-5.6-terra",
         "bedrock/converse/us.openai.gpt-5.6-luna",
+        "us.openai.gpt-6-astra",
+        "bedrock/converse/global.openai.gpt-6-astra",
     ],
 )
 def test_reasoning_effort_maps_to_reasoning_effort_for_openai_gpt5_converse(model, local_model_cost_map):
@@ -412,6 +414,7 @@ def test_reasoning_effort_maps_to_reasoning_effort_for_openai_gpt5_converse(mode
     [
         "us.openai.gpt-5.6-sol",
         "bedrock/converse/global.openai.gpt-5.6-luna",
+        "us.openai.gpt-6-astra",
     ],
 )
 def test_openai_gpt5_converse_never_forwards_thinking(model, local_model_cost_map):