Set up OpenAI ChatGPT Codex with LiteLLM on Amazon ECS and Amazon Bedrock

OpenAI ChatGPT Codex with LiteLLM can provide centralized enterprise controls for generative AI coding agents. These agents help developers understand repositories, write code, run tests, and complete multi-step engineering tasks. As organizations move from individual experimentation to managed adoption, teams need a consistent way to control model access and attribute consumption. They must also apply budgets and rate limits, and observe the model-access path.

OpenAI Codex (Codex) runs its task loop on the developer workstation. It reads local files and runs approved tools under its local sandbox and approval settings. Customers can still route model inference through infrastructure in the customer’s AWS account.

In this post, we walk you through deploying a customer-operated LiteLLM gateway on Amazon Elastic Container Service (Amazon ECS). We show how to connect it to an OpenAI model on Amazon Bedrock, and configure Codex to use the gateway’s Responses API. We also show how to validate semantic continuation, streaming, and function calling. Finally, we explain when direct AWS IAM Identity Center access or a managed gateway such as Portkey can be a better fit.

The complete implementation is available in the guidance-codex repository. For the primary path in this post, follow the LiteLLM on AWS quickstart.