Core Concept - Introduces the concept of "human-in-the-loop" middleware for Langchain agents, allowing human review and intervention in agent workflows [5][18] - Explains the agent's reasoning loop: reason, act, observe, and how human intervention fits into this loop [3][5] - Highlights the three decision types for human reviewers: approve, edit, and reject, and how these decisions guide the agent's subsequent actions [7] Technical Implementation - Demonstrates the integration of a Langchain agent with human-in-the-loop middleware in a Nextjs application for sending emails [2][17] - Emphasizes the importance of a checkpointer (using Redis database) to store the agent's state and enable resuming the workflow after human intervention [13][14] - Describes how the middleware intercepts tool calls (e g, sending emails) and pauses the agent's execution, awaiting human input [5][6] Benefits and Use Cases - Positions human-in-the-loop as a way to combine agent autonomy with human oversight, especially for actions with risk or requiring judgment [18][19] - Suggests use cases such as sending emails, updating records, or writing to external systems, where human review is valuable [19] - Underscores the flexibility of the middleware, allowing customization of interruption logic based on tool name, arguments, or runtime context [19][20] Practical Example - Provides a practical example of using the middleware to allow a human to revise an email drafted by the agent before it is sent [2][16] - Showcases how to reject a proposed action and provide feedback to the agent, influencing its subsequent behavior [16] - Mentions a publicly available repository (github com/christian broman/lunghat) for users to experiment with the human-in-the-loop concept [20]

Hi there, this is Christian from Langchain. Just a couple of weeks ago, we released version one of Langchain and Lang Graph. And one of the cool features of it is that it makes it really easy to stream events and results from the agent down to any type of front end that you're using, whether it's React, Vue, or Swelt.So, in this video, I want to build a little CHPT clone that shows you how you can build and create agent right in your Nex. js application. Every longchain agent maintains a state throughout it ...