How we built Agent Builder’s memory system

LangSmith's Agent Builder features a powerful memory system that allows its no-code AI agents to learn from user interactions and improve over time. This memory is cleverly implemented as a virtual filesystem, where an agent can read and write files containing its core instructions, skills, and accumulated knowledge. As a user provides corrections, the agent automatically updates its own instruction files, remembering preferences for future tasks without needing to be reminded. This iterative learning process allows a simple agent to evolve into a highly detailed and specialized assistant, all without the user ever manually editing a configuration file.