# HITL KIT > @hitl-kit/* — React primitives, Zod event schemas, composable decision gates, and LangGraph / AI-SDK / MCP adapters for human-in-the-loop agentic UIs. Components install via the shadcn CLI; packages live on npm. Part of akaOSS. - **Type:** MCP server - **Install:** `agentstack add mcp-akaieuan-hitl-kit` - **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior - **Seller:** [akaieuan](https://agentstack.voostack.com/s/akaieuan) - **Installs:** 0 - **Category:** [Developer Tools](https://agentstack.voostack.com/c/developer-tools) - **Latest version:** 0.1.0 - **License:** MIT - **Upstream author:** [akaieuan](https://github.com/akaieuan) - **Source:** https://github.com/akaieuan/HITL-KIT - **Website:** https://www.akaoss.dev/projects/hitl-kit ## Install ```sh agentstack add mcp-akaieuan-hitl-kit ``` Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent. ## About # HITL Kit > Human-in-the-loop primitives for agentic UIs. HITL Kit is part of [**akaOSS**](https://www.akaoss.dev) — the site, docs, [paper](https://www.akaoss.dev/paper), and [component registry](https://www.akaoss.dev/registry) live at [akaoss.dev](https://www.akaoss.dev). **This repo is the `@hitl-kit/*` library monorepo**: six npm packages, the LangGraph demo app, and design docs. [**Project page**](https://www.akaoss.dev/projects/hitl-kit) · [**Components gallery**](https://www.akaoss.dev/components) · [**Registry**](https://www.akaoss.dev/registry) · [**Paper**](https://www.akaoss.dev/paper) --- ## Why it exists 95% of enterprise AI pilots fail — not because the models are bad, but because we measure the wrong thing. Current benchmarks ask *"can the model complete this task autonomously?"* Deployment asks *"does it respect the user's authority, preserve their agency, and make them better over time?"* The gap between those two questions is where pilots die — and every primitive in this kit exists because something falls into it. The design discipline: each of the fifteen UI primitives is the physical embodiment of a specific claim from [An AI Measurement Problem](https://www.akaoss.dev/paper). The MiniTrace instantiates HotpotQA's supporting-facts requirement; the AI Generation Scale operationalises Dhillon et al.'s scaffolding findings; the Interrupt Card is the agency-preservation boundary. If a primitive can't be tied to a claim the paper defends, it doesn't ship. The packages below carry that protocol into real agent stacks. Full deep-dive: [akaoss.dev/projects/hitl-kit](https://www.akaoss.dev/projects/hitl-kit). ## Packages | Package | Version | Description | |---|---|---| | [`@hitl-kit/core`](https://www.npmjs.com/package/@hitl-kit/core) | 0.5.0 | Zod event schemas for human-in-the-loop AI primitives. Framework-agnostic protocol shared by every HITL Kit adapter. | | [`@hitl-kit/react`](https://www.npmjs.com/package/@hitl-kit/react) | 0.4.2 | `HitlEventRenderer`, a typed dispatcher that maps validated HITL events to React primitives. Pair with `@hitl-kit/core` and any shadcn-installed HITL primitives. | | [`@hitl-kit/gates`](https://www.npmjs.com/package/@hitl-kit/gates) | 0.2.0 | Composable decision gates (confidence, cost, scope, approval chain, rate limit). Pure functions that wrap any adapter's emit point and decide allow / deny / escalate. | | [`@hitl-kit/langgraph`](https://www.npmjs.com/package/@hitl-kit/langgraph) | 0.6.1 | LangGraph adapter. Emit schema-conformant HITL events from LangGraph `interrupt()` nodes and resume with typed `Command` payloads. | | [`@hitl-kit/ai-sdk`](https://www.npmjs.com/package/@hitl-kit/ai-sdk) | 0.7.1 | Vercel AI SDK adapter. Typed `tool()` wrappers that return schema-conformant HITL events so `` can dispatch them client-side. | | [`@hitl-kit/mcp`](https://www.npmjs.com/package/@hitl-kit/mcp) | 0.8.0 | MCP server exposing the 15 HITL primitive event kinds as MCP tools, so Claude Code, Cursor, Claude Desktop, and any MCP-aware client can emit schema-validated human-in-the-loop events. | --- ## Install The library packages install from npm: ```bash pnpm add @hitl-kit/core @hitl-kit/react ``` The UI primitives install via the shadcn CLI from the HITL Kit registry (served by the akaOSS site — these URLs keep working): ```bash npx shadcn@latest add https://www.hitlkit.dev/r/hitl-card.json ``` The CLI resolves registry dependencies (`hitl-utils`, `hitl-types`) and npm dependencies (`lucide-react`) automatically. Browse every primitive with copy-paste install commands at [akaoss.dev/registry](https://www.akaoss.dev/registry), and see them live at [akaoss.dev/components](https://www.akaoss.dev/components). --- ## Use the event renderer For agentic UIs, pair the components with `@hitl-kit/core` (Zod event schemas) and `@hitl-kit/react` (`HitlEventRenderer`): ```tsx import { createRegistry, HitlEventRenderer } from "@hitl-kit/react"; import { HitlCard } from "@/components/hitl/HitlCard"; const registry = createRegistry({ "hitl.card": (event) => ( ), }); // later, when your agent emits a validated HITL event: ; ``` The renderer validates the event at runtime via the shared Zod schema, narrows on `event.kind`, and mounts the primitive you registered for that kind. Works identically no matter which agent framework produced the event. --- ## Use with LangGraph `@hitl-kit/langgraph` turns LangGraph's native `interrupt()` / `Command({ resume })` primitive into a typed HITL event producer. The graph pauses, the UI renders a primitive via ``, the human acts, the graph resumes. End-to-end, no glue. ```bash pnpm add @hitl-kit/core @hitl-kit/react @hitl-kit/langgraph @langchain/langgraph ``` ```ts check import { StateGraph, interrupt } from "@langchain/langgraph"; import { createHitlCardInterrupt } from "@hitl-kit/langgraph"; // inside a node... 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; Command({ resume: { approved: true } }) causes this line to return { approved: true } ``` On the client, guard with `isHitlInterrupt` and render through the same ``. Every primitive has a matching `createInterrupt` helper that validates against the core Zod schema at emit time, so a malformed event throws inside the graph node rather than surfacing on the client. --- ## Use with Vercel AI SDK `@hitl-kit/ai-sdk` provides 15 typed `tool()` wrappers — one per HITL Kit primitive — that return validated HITL events as tool results. Since AI SDK has no native interrupt primitive, the adapter returns "awaiting human" as a tool-call result; the consumer renders the event and appends a follow-up user message to continue the conversation. ```bash pnpm add @hitl-kit/core @hitl-kit/react @hitl-kit/ai-sdk ai zod ``` ```ts import { generateText } from "ai"; import { hitlCardTool, approveRejectTool, allHitlTools } from "@hitl-kit/ai-sdk"; const result = await generateText({ model, messages, tools: { requestHumanReview: hitlCardTool({ description: "Request human review of a citation before writing it.", }), requestApproval: approveRejectTool(), }, }); // If the model calls requestHumanReview, the tool result is a validated HitlCardEvent. // Or pass all 15 at once: tools: allHitlTools ``` Client side, filter for HITL tool results with `isHitlToolResult` and render each through ``. --- ## Add gates A gate is a pure decision function: confidence too low? cost over budget? scope outside what's allowed? deny — and (default) surface a HITL escalation card so the human can override. Same renderer pipeline handles allow- and block-paths. ```bash pnpm add @hitl-kit/gates ``` ```ts check import { composeGates, confidenceGate, costGate, scopeGate, rateLimitGate, inMemoryStore, } from "@hitl-kit/gates"; const store = inMemoryStore(); const gates = [ confidenceGate({ min: 0.85 }), costGate({ maxUsd: 0.10 }), scopeGate({ allowed: ["read:files", "read:web"] }), rateLimitGate({ store, key: (ctx) => ctx.signals?.userId ?? "anon", max: 30, windowSec: 60 }), ]; ``` Wire them in via the adapter helpers: ```ts // LangGraph import { withGates } from "@hitl-kit/langgraph"; const gated = await withGates(payload, gates, { signals }); const approval = interrupt(gated); // Vercel AI SDK import { withGates } from "@hitl-kit/ai-sdk"; const tool = withGates(hitlCardTool(), gates, { signals: (input) => deriveSignals(input) }); // MCP — gates configured at server creation import { createHitlKitServer } from "@hitl-kit/mcp"; const server = createHitlKitServer({ gates, onDeny: "escalate" }); ``` When a gate denies with the default `onDeny`, the result is the gate's escalation `HitlEvent` — feed it to the same `` you already use. Full details in [packages/gates/README.md](./packages/gates/README.md). --- ## Use with MCP · Claude Code, Cursor, Claude Desktop `@hitl-kit/mcp` is an MCP server that exposes all 15 primitive event kinds as tools. Drop it into any MCP-aware client and every client's agent can emit schema-validated HITL events. No per-client adapter code. ### Claude Desktop Edit `~/Library/Application Support/Claude/claude_desktop_config.json` (macOS) or `%APPDATA%\Claude\claude_desktop_config.json` (Windows): ```json { "mcpServers": { "hitl-kit": { "command": "npx", "args": ["-y", "@hitl-kit/mcp"] } } } ``` ### Claude Code ```bash claude mcp add hitl-kit npx -y @hitl-kit/mcp ``` ### Cursor Cursor Settings → MCP Servers → Add, same JSON as Claude Desktop. Once registered and the client is restarted, `hitl_interrupt_card`, `hitl_qa_flow`, and 13 more tools are available. Each validates input against the core Zod schema and returns a JSON `HitlEvent` ready for your UI. --- ## Demo app [`apps/demo-langgraph`](./apps/demo-langgraph) is a minimal Next.js app that exercises the whole pipeline end-to-end: a LangGraph with a real `interrupt()` node, the Interrupt Card rendered via ``, approval, and `Command({ resume })`. It also has tabs for the AI SDK flow (`/ai-sdk`), gates (`/gates`), and the v0.6a primitives (`/diff`, `/citation`, `/plan`, `/tool-call`). ```bash pnpm install pnpm --filter demo-langgraph dev # http://localhost:3100 ``` --- ## What's in this repo ``` . ├── packages/ │ ├── core/ @hitl-kit/core (Zod event schemas) │ ├── react/ @hitl-kit/react (HitlEventRenderer) │ ├── gates/ @hitl-kit/gates (5 composable decision gates) │ ├── langgraph/ @hitl-kit/langgraph (interrupt helpers + withGates) │ ├── ai-sdk/ @hitl-kit/ai-sdk (Vercel AI SDK tool wrappers + withGates) │ └── mcp/ @hitl-kit/mcp (MCP stdio server with gate hooks, hitl-kit-mcp bin) ├── apps/ │ └── demo-langgraph/ End-to-end LangGraph interrupt/resume demo (port 3100) ├── docs/ │ ├── api-unification.md v0.7 API unification design doc │ └── EVAL_KIT_BRIEF.md Historical design brief ├── .github/workflows/ci.yml Build → typecheck → test → audit └── CONTRIBUTING.md Verification and branch protocol ``` The studio site, the paper source, and the shadcn registry source moved to [akaieuan/akaOSS](https://github.com/akaieuan/akaOSS) and are served at [akaoss.dev](https://www.akaoss.dev) and [hitlkit.dev](https://www.hitlkit.dev). Registry install URLs (`hitlkit.dev/r/*.json`) are unaffected. --- ## Development ```bash pnpm install pnpm packages:build # build all @hitl-kit/* packages via tsup pnpm packages:typecheck # tsc --noEmit in every package pnpm test # vitest across packages/*/src pnpm verify # all three, in order — run before pushing ``` ### Testing Vitest runs against `packages/*/src` only. Currently **63 tests across 13 files**: round-trip parse for every event kind + exhaustiveness + frozen fixtures in `@hitl-kit/core`, every gate factory, compose, store, rate-limit, and approval chain in `@hitl-kit/gates`, and integration tests per adapter (`withGates` allow + escalate + throw). ```bash pnpm test # single run pnpm test:watch # watch mode ``` --- ## Contributing Issues and PRs welcome. Open an issue first for substantial changes so we can agree on scope. The verification and branch protocol is documented in [CONTRIBUTING.md](./CONTRIBUTING.md) — `pnpm verify` before every push; CI runs build → typecheck → test plus a dependency audit that fails on high or critical advisories. Good first contributions: - Accessibility improvements (ARIA, keyboard navigation) — the v0.7 a11y pass is planned in [docs/api-unification.md](./docs/api-unification.md) - Better Zod schema types in `packages/core` - Documentation fixes Component/registry contributions (the 15 UI primitives) now belong in [akaieuan/akaOSS](https://github.com/akaieuan/akaOSS). --- ## License [MIT](./LICENSE). Do what you want. --- ## Credits Built by [Ieuan King](https://aka4uh.com) ([@akaieuan](https://x.com/akaieuan)). The component set was originally extracted from [Agatha](https://aka4uh.com), a research-agent workspace, and generalized into an open primitive library. The perspective paper behind the project — [An AI Measurement Problem](https://www.akaoss.dev/paper) — argues for the Assist-Not-Complete paradigm: evaluate AI on whether it assists humans without displacing them, not on whether it can finish the task alone. ## Source & license This open-source MCP server is cataloged on AgentStack and links to its original source — we do not rehost the code. - **Author:** [akaieuan](https://github.com/akaieuan) - **Source:** [akaieuan/HITL-KIT](https://github.com/akaieuan/HITL-KIT) - **License:** MIT - **Homepage:** https://www.akaoss.dev/projects/hitl-kit Install and usage instructions live in the source repository linked above. ## Pricing - **Free** — Free ## Security capabilities Automated source analysis of v0.1.0 — what this tool can access: - **Network access:** no - **Filesystem access:** no - **Shell / process execution:** no - **Environment & secrets:** no - **Dynamic code execution:** no *"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.* ## Versions - **0.1.0** — security scan: passed — Imported from the upstream source. ## Links - Listing page: https://agentstack.voostack.com/l/mcp-akaieuan-hitl-kit - Seller: https://agentstack.voostack.com/s/akaieuan - Browse the marketplace: https://agentstack.voostack.com/browse --- Listed on AgentStack — the marketplace for AI agent skills and MCP servers. 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