underthesea

Why we included this project

Most agent libraries force you to install a vendor SDK before you can do anything, but Underthesea keeps the whole harness on the Python standard library. The same pip install gives you an agent that works with OpenAI, Azure OpenAI, Anthropic, and Google Gemini, plus tool calling, streaming, and long-running sessions with context reset and handoff. Tracing can go to local files or Langfuse, and an A2A server exposes your agent over HTTP with a bundled chat UI. Underneath sits a long-standing set of Vietnamese NLP tools, covering word segmentation, part-of-speech tagging, sentence splitting, and text normalization. For teams building assistants that need to understand Vietnamese, one install covers both the language processing and the agent layer.