[Bug]: Claude Code with Qwen Models unknown variant `anthropic_beta`,

[irfansofyana]

What happened?

A bug happened!

Hi, I just recently upgraded my litellm proxy to version v1.80.0-stable and now the integration between claude code -> litellm -> bedrock is broken due following error:

API Error: 400 {"error":{"message":"litellm.BadRequestError: BedrockException - {"message":"The model returned the following errors:
{\"code\":\"validation_error\",\"message\":\"Failed to deserialize the JSON body into the target type: unknown variant anthropic_beta, expected one of
audio, frequency_penalty, function_call, functions, logit_bias, logprobs, max_completion_tokens, max_tokens, messages, metadata, modalities,
model, n, parallel_tool_calls, prediction, presence_penalty, prompt_cache_key, reasoning_effort, response_format, safety_identifier, seed,
service_tier, stop, store, stream, stream_options, temperature, text, tool_choice, tools, top_k, top_logprobs, top_p, user, verbosity,
web_search_options at line 1 column 93325\",\"param\":null,\"type\":\"invalid_request_error\"}"}. Received Model
Group=bedrock/us/qwen3-coder-480b-test\nAvailable Model Group Fallbacks=None","type":null,"param":null,"code":"400"}}

Relevant log output

API Error: 400 {"error":{"message":"litellm.BadRequestError: BedrockException - {\"message\":\"The model returned the following errors: 
    {\\\"code\\\":\\\"validation_error\\\",\\\"message\\\":\\\"Failed to deserialize the JSON body into the target type: unknown variant `anthropic_beta`, expected one of 
    `audio`, `frequency_penalty`, `function_call`, `functions`, `logit_bias`, `logprobs`, `max_completion_tokens`, `max_tokens`, `messages`, `metadata`, `modalities`, 
    `model`, `n`, `parallel_tool_calls`, `prediction`, `presence_penalty`, `prompt_cache_key`, `reasoning_effort`, `response_format`, `safety_identifier`, `seed`, 
    `service_tier`, `stop`, `store`, `stream`, `stream_options`, `temperature`, `text`, `tool_choice`, `tools`, `top_k`, `top_logprobs`, `top_p`, `user`, `verbosity`, 
    `web_search_options` at line 1 column 93325\\\",\\\"param\\\":null,\\\"type\\\":\\\"invalid_request_error\\\"}\"}. Received Model 
    Group=bedrock/us/qwen3-coder-480b-test\nAvailable Model Group Fallbacks=None","type":null,"param":null,"code":"400"}}

Are you a ML Ops Team?

No

What LiteLLM version are you on ?

v1.80.0-stable

Twitter / LinkedIn details

No response

[irfansofyana]

What i have done is trying to drop this param but still unlucky

[irfansofyana]

here is my config in litellm:

 - model_name: bedrock/us/qwen3-coder-480b
        litellm_params:
          model: bedrock/arn:aws:bedrock:us-west-2::foundation-model/qwen.qwen3-coder-480b-a35b-v1:0
          aws_region_name: us-west-2
          aws_role_name: arn:aws:iam::xxxxx:role/AWSBedrockAppRole-Litellm
          aws_session_name: "LiteLLM"
          drop_params: true
          additional_drop_params: ["thinking", "reasoning_effort", "anthropic_beta"]