# interrupt()

Pauses the graph before a risky node. It resumes when the user approves.

AI developers · Part 06: LangChain / LangGraph · Card 13 of 14 · Last updated 2026-10-13

## Analogy

A confirm() dialog that can wait days, because the state is saved in the meantime.

## In an agent

The building block for human-in-the-loop approval on write actions.

## Practice

### Flashcards

- **What is human-in-the-loop?** The agent pauses for a person to approve an action before it runs.
- **Interview: what does LangGraph add to LangChain?** Explicit graphs with state, checkpoints, interrupts and routing, so complex agents are easier to control.

## Questions people ask

### What does interrupt do in LangGraph?

interrupt pauses the graph at a chosen point, usually just before a risky node such as sending an email or issuing a refund. The state is saved by the checkpointer, so the pause can last minutes or days. When the user approves, the graph resumes from that exact point.

### How do I add human approval to a LangGraph agent?

Call interrupt in the node before the risky action, or interrupt before that node when compiling the graph, and use a checkpointer. Show the proposed action to a person. When they approve, invoke the graph again with the same thread_id and a resume command, and it continues from where it paused.

## Related concepts

- [LangGraph.js](https://studyvisually.com/learn/tech/ai-developers/langchain-langgraph/langgraph)
- [Graph state](https://studyvisually.com/learn/tech/ai-developers/langchain-langgraph/graph-state)
- [Conditional edges](https://studyvisually.com/learn/tech/ai-developers/langchain-langgraph/conditional-edges)
- [Checkpointing](https://studyvisually.com/learn/tech/ai-developers/langchain-langgraph/checkpointing)

Web page: https://studyvisually.com/learn/tech/ai-developers/langchain-langgraph/interrupt
Study this card in the app: https://studyvisually.com/app/learn?category=ai-developers&card=interrupt