@hitl-kit/langgraph

LangGraph adapter for HITL Kit. Emit schema-conformant HITL events from LangGraph interrupt() nodes and resume with typed Command payloads.

pnpm add @hitl-kit/core @hitl-kit/langgraph @langchain/langgraph

@langchain/langgraph is a peer dependency; the version you install is up to you.

Why LangGraph first

LangGraph is the only mainstream TS agent framework with a native interrupt() / Command({ resume }) primitive explicitly designed for human checkpoints. That primitive maps 1:1 to the Assist-Not-Complete thesis: pause the graph, wait for structured human input, resume.

The adapter is a thin translation layer:

• Emit side: helpers like createHitlCardInterrupt({...}) produce a validated HitlInterruptPayload that wraps a Zod-checked HitlEvent from @hitl-kit/core. You pass the payload directly into interrupt().
• Receive side: isHitlInterrupt(value) is a type guard you use in your UI layer to route to <HitlEventRenderer /> from @hitl-kit/react.

Because the event field is the exact shape <HitlEventRenderer /> expects, no manual mapping is needed.

Usage

Emit a HITL interrupt inside a graph node

import { StateGraph } from "@langchain/langgraph";
import { interrupt } from "@langchain/langgraph";
import { createHitlCardInterrupt } from "@hitl-kit/langgraph";

const graph = new StateGraph(State)
  .addNode("review-citation", async (state) => {
    const approval = interrupt(
      createHitlCardInterrupt({
        variant: "review",
        title: "Citation needs verification",
        subtitle: "IPCC 2023 · p. 12",
        steps: [
          { label: "Flagged by agent", done: true },
          { label: "Confirm", done: false },
        ],
        runLabel: "Confirm & continue",
      }),
    );
    // Graph pauses here.
    // When the UI sends `Command({ resume: { approved: true } })`,
    // `approval` becomes `{ approved: true }` and execution continues.
    return { ...state, approved: approval.approved };
  });

Render the interrupt on the client

import { HitlEventRenderer } from "@hitl-kit/react";
import { isHitlInterrupt } from "@hitl-kit/langgraph";
import { HitlCard } from "@/components/hitl/HitlCard";

function AgentRunner({ interruptValue, onResume }) {
  if (!isHitlInterrupt(interruptValue)) return null;

  return (
    <HitlEventRenderer
      event={interruptValue.event}
      registry={{
        "hitl.card": (ev) => (
          <HitlCard
            config={{
              id: ev.id ?? "default",
              kind: ev.variant,
              title: ev.title,
              subtitle: ev.subtitle,
              steps: ev.steps,
              runLabel: ev.runLabel,
              editPlaceholder: ev.editPlaceholder,
              openTab: "human",
            }}
          />
        ),
      }}
      onAction={(action) => onResume(action)}
    />
  );
}

Resume the graph

On user approval, POST a resume command back to your graph runner:

await graph.invoke(
  new Command({ resume: { approved: true } }),
  { configurable: { thread_id: threadId } },
);

Helpers (one per primitive)

Every HITL Kit primitive has a matching interrupt helper:

| Helper | Event kind | |---|---| | createHitlCardInterrupt | hitl.card | | createSubagentStatusInterrupt | subagent.status | | createMiniTraceInterrupt | trace.mini | | createAiGenerationScaleInterrupt | scale.ai_generation | | createContextChipsInterrupt | chips.context | | createQAFlowInterrupt | qa.flow | | createWritingAgentInterrupt | agent.writing | | createResearchAgentInterrupt | agent.research | | createBatchQueueInterrupt | batch.queue | | createSearchResultInterrupt | result.search | | createApproveRejectInterrupt | approval.binary | | createDiffResultInterrupt (v0.6a) | result.diff | | createCitationResultInterrupt (v0.6a) | result.citation | | createEditablePlanInterrupt (v0.6a) | plan.editable | | createToolCallPreviewInterrupt (v0.6a) | tool.call |

Each helper validates the payload against the corresponding Zod schema from @hitl-kit/core and throws synchronously if the event is malformed. No more shipping a broken event to the UI.

isEditablePlanResume(value) is a runtime type guard for the resume payload an editable-plan interrupt expects ({ steps: PlanStep[]; cancelled?: boolean }).

Part of HITL Kit

• Schemas → @hitl-kit/core
• Renderer → @hitl-kit/react
• Components → hitlkit.dev/registry
• Paper → hitlkit.dev/paper
• Live demo → apps/demo-langgraph (Run pnpm --filter demo-langgraph dev)

License

MIT License

Copyright (c) 2023-2026 Ubik, Inc.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.