From 9309ebdd3537368585e88b26416960f3d98f68ec Mon Sep 17 00:00:00 2001
From: mateo-berri <277851410+mateo-berri@users.noreply.github.com>
Date: Thu, 21 May 2026 00:35:09 +0000
Subject: [PATCH] fix(bedrock): warn when invoke transformation strips
 output_config

The Bedrock Invoke chat and messages transformations strip output_config
when neither supports_output_config nor any supports_*_reasoning_effort
flag is set in the model JSON. This was silent; emit a verbose_logger
warning when the strip actually removes a present output_config so newly
released models (where the JSON entry hasn't caught up yet) surface a
clear log line instead of dropping the effort parameter without notice.
---
 .../anthropic_claude3_transformation.py              | 12 +++++++++++-
 .../anthropic_claude3_transformation.py              | 11 ++++++++++-
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/litellm/llms/bedrock/chat/invoke_transformations/anthropic_claude3_transformation.py b/litellm/llms/bedrock/chat/invoke_transformations/anthropic_claude3_transformation.py
index 1d615d8df7e..d9599b8b9c4 100644
--- a/litellm/llms/bedrock/chat/invoke_transformations/anthropic_claude3_transformation.py
+++ b/litellm/llms/bedrock/chat/invoke_transformations/anthropic_claude3_transformation.py
@@ -3,6 +3,7 @@ from typing import TYPE_CHECKING, Any, List, Optional
 import httpx
 
 from litellm.anthropic_beta_headers_manager import filter_and_transform_beta_headers
+from litellm.litellm_core_utils.litellm_logging import verbose_logger
 from litellm.litellm_core_utils.prompt_templates.factory import (
     convert_to_anthropic_image_obj,
 )
@@ -178,7 +179,16 @@ class AmazonAnthropicClaudeConfig(AmazonInvokeConfig, AnthropicConfig):
             )
             or AnthropicConfig._model_supports_effort_param(model)
         ):
-            anthropic_request.pop("output_config", None)
+            if anthropic_request.pop("output_config", None) is not None:
+                verbose_logger.warning(
+                    "Bedrock Invoke: stripping unsupported `output_config` for "
+                    "model=%s — neither `supports_output_config` nor any "
+                    "`supports_*_reasoning_effort` flag is set in "
+                    "model_prices_and_context_window.json. Add the capability "
+                    "flag to the model JSON entry if this model accepts "
+                    "`output_config`.",
+                    model,
+                )
         if "anthropic_version" not in anthropic_request:
             anthropic_request["anthropic_version"] = self.anthropic_version
 
diff --git a/litellm/llms/bedrock/messages/invoke_transformations/anthropic_claude3_transformation.py b/litellm/llms/bedrock/messages/invoke_transformations/anthropic_claude3_transformation.py
index add9cb031b3..69b61298d33 100644
--- a/litellm/llms/bedrock/messages/invoke_transformations/anthropic_claude3_transformation.py
+++ b/litellm/llms/bedrock/messages/invoke_transformations/anthropic_claude3_transformation.py
@@ -569,7 +569,16 @@ class AmazonAnthropicClaudeMessagesConfig(
             )
             or AnthropicConfig._model_supports_effort_param(model)
         ):
-            anthropic_messages_request.pop("output_config", None)
+            if anthropic_messages_request.pop("output_config", None) is not None:
+                verbose_logger.warning(
+                    "Bedrock Invoke: stripping unsupported `output_config` for "
+                    "model=%s — neither `supports_output_config` nor any "
+                    "`supports_*_reasoning_effort` flag is set in "
+                    "model_prices_and_context_window.json. Add the capability "
+                    "flag to the model JSON entry if this model accepts "
+                    "`output_config`.",
+                    model,
+                )
 
         # 5b. Remove `custom` field from tools (Bedrock doesn't support it)
         # Claude Code sends `custom: {defer_loading: true}` on tool definitions,