Worked on the sst/opencode repository to deliver cross-region inference enhancements for Japanese models in Amazon Bedrock. Focused on backend development using TypeScript, the work automated the assignment of the jp. prefix to model IDs for the Tokyo region, enabling seamless cross-region inference and reducing manual configuration. By integrating this logic at the provider level, the solution streamlined regional deployment flows and improved the user experience for Japanese models. The implementation centered on API integration and backend logic, ensuring that model ID handling was consistent and reliable during cross-region requests, with all changes documented and consolidated for maintainability.