Building on the initial limited preview of OpenAI models on Amazon Bedrock, AWS has added GPT-5.5, GPT-5.4, and OpenAI Codex to the preview lineup. Bedrock Managed Agents can now be configured to use OpenAI-backed models as their reasoning layer, enabling organizations already invested in the Bedrock agent framework to swap or supplement Anthropic and Amazon models with OpenAI equivalents without changing orchestration code. The expansion is significant for platform teams managing multi-model inference budgets through a single API surface. Codex availability on Bedrock is particularly relevant for teams exploring code-generation pipelines anchored to AWS infrastructure, as it removes the need for a separate OpenAI API integration. All additions remain in limited preview, so production reliance should be deferred until GA status is confirmed.