During July 2025, Chengnan Cai developed Doubao LLM model support for the hacksider/trae-agent repository, focusing on backend extensibility and unified model orchestration. He introduced a dedicated client wrapper for Doubao, integrating it into the main LLM client factory to streamline onboarding of additional models. His work included implementing API key and base URL initialization, chat history management, and chat completion handling with optional tool support, all using Python. This feature-focused iteration enhanced the system’s interoperability and maintainability, addressing the need for smoother client experiences and faster integration of new LLMs without requiring major changes to the existing architecture.