AWS and OpenAI Preview Managed Agent Service BMA

Details

Amazon Bedrock Managed Agents (BMA), jointly developed by AWS and OpenAI, was released in preview on September 29, 2026
BMA automates model invocation, tool execution, conversation state maintenance, and context compression through the Codex harness, reducing the burden of direct implementation for developers
When a session is created by specifying the model, instructions, tools, and execution environment, BMA handles the loop, and commands are executed in the AgentCore Runtime of the customer's account
In the example app AI Document Studio, three document generation flows were tested using the GPT-6.1 Sol model, with all completing within 1 minute (maximum 53.03 seconds)
During the preview period, there are no BMA-specific fees, and only model inference and AWS resource costs are incurred; it is available in three regions, including us-east-1
The OpenAI Python SDK can be used as is, with only the base_url and authentication method changed to AWS credentials
Sub-agents and code-based tool calls are not yet supported, and session input is limited to text only

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