@langgraph-js/sdk/dist/server/createState.js

The UI SDK for LangGraph - seamlessly integrate your AI agents with frontend interfaces

import { Annotation } from "@langchain/langgraph";
/**
 * create state for langgraph
 * @example
 * export const GraphState = createState(createReactAgentAnnotation(), ModelState, SwarmState).build({
 *   current_plan: createDefaultAnnotation<Plan | null>(() => null),
 *   title: createDefaultAnnotation<string>(() => ""),
 *});
 */
export const createState = (...parents) => {
    return {
        build: (state = {}) => {
            return Annotation.Root(Object.assign({}, ...parents.map((p) => p.spec), state));
        },
    };
};
export const createDefaultAnnotation = (defaultValue) => Annotation({
    reducer: (_, a) => a,
    default: defaultValue,
});