AWS Adds Structured Outputs for Claude Models on Amazon Bedrock

Amazon Web Services now supports structured outputs for all available Anthropic Claude models on Amazon Bedrock, as detailed in a company blog post. It works on both the bedrock runtime and bedrock mantle endpoints, wherever the models are available.

Structured outputs use constrained decoding to generate JSON that matches a developer defined schema. AWS also supports strict tool use, which restricts tool parameters to the specified types, required fields, and allowed values.

The feature works with batch inference, streaming responses, and cross Region inference through the bedrock runtime endpoint. Bedrock compiles a grammar when it receives a new schema and caches it for 24 hours, so the first request can take longer than later requests using the same schema.