diff --git a/litellm/llms/bedrock/common_utils.py b/litellm/llms/bedrock/common_utils.py index 89b42f5e94..65d237bdbd 100644 --- a/litellm/llms/bedrock/common_utils.py +++ b/litellm/llms/bedrock/common_utils.py @@ -797,7 +797,7 @@ class BedrockEventStreamDecoderBase: def get_anthropic_beta_from_headers(headers: dict) -> List[str]: """ Extract anthropic-beta header values and convert them to a list. - Supports comma-separated values from user headers. + Supports both JSON array format and comma-separated values from user headers. Used by both converse and invoke transformations for consistent handling of anthropic-beta headers that should be passed to AWS Bedrock. @@ -812,8 +812,25 @@ def get_anthropic_beta_from_headers(headers: dict) -> List[str]: if not anthropic_beta_header: return [] - # Split comma-separated values and strip whitespace - return [beta.strip() for beta in anthropic_beta_header.split(",")] + # If it's already a list, return it + if isinstance(anthropic_beta_header, list): + return anthropic_beta_header + + # Try to parse as JSON array first (e.g., '["interleaved-thinking-2025-05-14", "claude-code-20250219"]') + if isinstance(anthropic_beta_header, str): + anthropic_beta_header = anthropic_beta_header.strip() + if anthropic_beta_header.startswith("[") and anthropic_beta_header.endswith("]"): + try: + parsed = json.loads(anthropic_beta_header) + if isinstance(parsed, list): + return [str(beta).strip() for beta in parsed] + except json.JSONDecodeError: + pass # Fall through to comma-separated parsing + + # Fall back to comma-separated values + return [beta.strip() for beta in anthropic_beta_header.split(",")] + + return [] class CommonBatchFilesUtils: