MISSING_CHECKPOINTER

You are attempting to use built-in LangGraph persistence without providing a checkpointer.

This happens when a checkpointer is missing in the compile() method of StateGraph or entrypoint.

Troubleshooting

The following may help resolve this error:

• Initialize and pass a checkpointer to the compile() method of StateGraph or entrypoint.

import { InMemorySaver, StateGraph } from "@langchain/langgraph";
const checkpointer = new InMemorySaver();

// Graph API
import { StateGraph } from "@langchain/langgraph";
const graph = new StateGraph(...).compile({ checkpointer });

// Functional API
import { entrypoint } from "@langchain/langgraph";
const workflow = entrypoint(
    { checkpointer, name: "workflow" },
    async (messages: string[]) => {
        // ...
    }
);

• Use the LangGraph API so you don't need to implement or configure checkpointers manually. The API handles all persistence infrastructure for you.

Related

• Read more about persistence.