Harrison Chase created LangChain and co-founded the company that develops LangChain, LangGraph, and LangSmith. His writing and talks focus on the engineering around AI agents: supplying context, controlling execution, and evaluating behavior.[1][2][4]
Start with The rise of context engineering →
Background
Chase studied statistics and computer science at Harvard. In a Latent Space interview, he described learning programming and data science through sports analytics, where predictions could be compared with the next game. He subsequently worked in machine learning at Kensho and Robust Intelligence. He recalled building a hackathon system at Robust Intelligence that answered questions using Notion and Slack, an early example of the data-connected language-model applications that LangChain would support.[3][8]
Career
Chase released the first LangChain package in late 2022, then teamed up with Ankush Gola to establish the company in early 2023. The original package helped developers connect language models with application data and tools. In his three-year retrospective, Chase describes the shift from prototyping chatbots toward deploying agents that take actions. The company expanded into LangGraph for agent execution and LangSmith for observing, evaluating, and deploying systems. Chase is its co-founder and chief executive.[1][2][9]
Contributions
LangGraph gives developers a way to define the steps and state of an agent as a graph, including loops. An agent might retrieve documents, judge whether they answer the question, and try another search. A developer can control which transitions are allowed instead of leaving every decision to the model. The LangChain team introduced the library in January 2024. It belongs to the company’s work under Chase’s leadership; that does not establish that he personally authored every component.[5]
Ideas
Context engineering
Chase uses context engineering to describe the systems that supply a model with instructions, information, and tools at the moment it needs them. In his 2025 essay, he argues that unreliable agents often lack the right context. This moves debugging beyond rewriting a single prompt: an engineer must inspect how earlier actions changed the information available at a later step. His claim is an engineering perspective, not a guarantee that context changes can fix every model failure.[4]
Inspecting long-running agents
In a 2026 Sequoia interview, Chase explains why traces matter for agents that act repeatedly. A trace records the calls and intermediate results that produced an outcome, helping an engineer reconstruct what the model saw when it made a decision. He also discusses file systems as a way to store information outside a limited context window. These ideas connect agent architecture with practical supervision: inspect the run, identify the failure, change the system, and evaluate the change.[6]
Tools, writing & talks
Writing, research & talks
Start here
The rise of context engineeringlangchain.comStart with this short essay on the information and tools an agent needs at each step. It provides vocabulary for diagnosing unreliable behavior.
Start with this explanation of how an agent chooses the information a model sees. It connects prompts, memory and tool output to concrete engineering decisions.
Authored essay[4]- The Future of Inference Market & Model Routing: Commodity or Increasing in Value? | LangChain CEOyoutube.com
LangChain's CEO discusses whether inference routing commoditizes, why better models force harness code to be deleted, the open agent memory layer, and what 1,000x more agent requests means for cost and engineering team size.
Catalog workOriginal source Harrison Chase of LangChain breaks agents into harness, model and context, and argues when teams should own each part, with evals as the way to keep control of their own intelligence. Includes Q&A.
Catalog workOriginal sourceAn X post arguing that who controls your agent's memory is inseparable from the harness, and that open harnesses avoid vendor lock-in. A strategic argument to read, not a tool or library.
Catalog workOriginal sourceHarrison Chase frames agent memory as semantic (facts), episodic (past experiences as few-shot examples) and procedural (evolving instructions), updated either in the hot path or by a background process. Applied to an email triage assistant built on LangGraph.
Catalog workOriginal source- Reflections on Three Years of Building LangChainlangchain.com
Chase’s account of the transition from a Python side project to frameworks and infrastructure for production agents.
Authored retrospective[2] - Context Engineering Our Way to Long-Horizon Agentssequoiacap.com
An interview on traces, file systems, memory, and the engineering needed to supervise agents over longer tasks.
Interview[6]