feat(create-langgraph): allow user to generate a langgraph config file (#1833)

Author: christian-bromann

.changeset/afraid-ants-dance.md

@@ -0,0 +1,5 @@
+---
+"create-langgraph": minor
+---
+
+feat(create-langgraph): allow user to generate a langgraph config file

libs/create-langgraph/README.md

@@ -0,0 +1,216 @@
+# create-langgraph
+
+[![npm version](https://img.shields.io/npm/v/create-langgraph.svg)](https://www.npmjs.com/package/create-langgraph)
+[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
+
+The official scaffolding tool for [LangGraph.js](https://langchain-ai.github.io/langgraphjs/) projects. Quickly bootstrap new LangGraph applications from curated templates or generate configuration files for existing projects.
+
+## Quick Start
+
+Create a new LangGraph project with a single command:
+
+```bash
+# Using npm
+npm init langgraph@latest
+
+# Using yarn
+yarn create langgraph
+
+# Using pnpm
+pnpm create langgraph
+
+# Using bun
+bunx create-langgraph
+```
+
+Follow the interactive prompts to select a template and configure your project.
+
+## Templates
+
+Choose from a variety of production-ready templates:
+
+| Template                                                                             | Description                                                     |
+| ------------------------------------------------------------------------------------ | --------------------------------------------------------------- |
+| [**New LangGraph Project**](https://github.com/langchain-ai/new-langgraphjs-project) | A simple, minimal chatbot with memory                           |
+| [**ReAct Agent**](https://github.com/langchain-ai/react-agent-js)                    | A flexible agent that can be extended with many tools           |
+| [**Memory Agent**](https://github.com/langchain-ai/memory-agent-js)                  | A ReAct-style agent with persistent memory across conversations |
+| [**Retrieval Agent**](https://github.com/langchain-ai/retrieval-agent-template-js)   | An agent with retrieval-based question-answering                |
+| [**Data-enrichment Agent**](https://github.com/langchain-ai/data-enrichment-js)      | An agent that performs web searches and organizes findings      |
+
+### Using a Specific Template
+
+Skip the interactive prompt by specifying a template directly:
+
+```bash
+npx create-langgraph@latest my-project --template react-agent-js
+```
+
+Available template IDs:
+
+- `new-langgraph-project-js`
+- `react-agent-js`
+- `memory-agent-js`
+- `retrieval-agent-js`
+- `data-enrichment-js`
+
+## Commands
+
+### `create-langgraph [path]`
+
+Creates a new LangGraph project at the specified path.
+
+```bash
+npx create-langgraph@latest my-awesome-agent
+```
+
+**Options:**
+
+- `-t, --template <template>` — Use a specific template (skips interactive selection)
+
+**What it does:**
+
+1. Downloads the selected template from GitHub
+2. Extracts it to your target directory
+3. Optionally initializes a Git repository
+4. Provides next steps for getting started
+
+### `create-langgraph config [path]`
+
+Scans your project for LangGraph agents and generates a `langgraph.json` configuration file.
+
+```bash
+# In your project directory
+npx create-langgraph@latest config
+
+# Or specify a path
+npx create-langgraph@latest config ./my-project
+```
+
+This command is useful when:
+
+- You have an existing project and want to add LangGraph Platform support
+- You've added new agents and need to update your configuration
+- You want to automatically detect all agents in your codebase
+
+## Agent Detection
+
+The `config` command automatically detects LangGraph agents defined using these patterns:
+
+### ESM (ES Modules)
+
+```typescript
+// Using createAgent
+export const agent = createAgent({ model, tools });
+
+// Using StateGraph
+export const graph = new StateGraph(annotation).compile();
+
+// Using workflow builder pattern
+export const app = workflow.compile();
+```
+
+### CommonJS
+
+```javascript
+// Using module.exports
+module.exports.agent = createAgent({ model, tools });
+module.exports.graph = workflow.compile();
+
+// Using exports shorthand
+exports.myAgent = createAgent({ model, tools });
+```
+
+### What Gets Detected
+
+The scanner looks for:
+
+- `createAgent()` function calls
+- `new StateGraph(...).compile()` patterns
+- `workflow.compile()` or `builder.compile()` patterns
+
+**Important:** Only **exported** agents are included in the generated configuration. Unexported agents will be listed as warnings so you can add the `export` keyword if needed.
+
+## Generated Configuration
+
+The `config` command generates a `langgraph.json` file like this:
+
+```json
+{
+  "node_version": "20",
+  "graphs": {
+    "agent": "./src/agent.ts:agent",
+    "searchAgent": "./src/search.ts:searchAgent"
+  },
+  "env": ".env"
+}
+```
+
+The configuration includes:
+
+- **node_version** — Detected from your current Node.js version
+- **graphs** — Map of agent names to their file paths and export names
+- **env** — Path to `.env` file (if one exists)
+
+## Project Structure
+
+After scaffolding, your project will have this structure:
+
+```txt
+my-project/
+├── src/
+│   └── agent.ts       # Your LangGraph agent
+├── langgraph.json     # LangGraph configuration
+├── package.json
+├── tsconfig.json
+└── .env.example       # Environment variables template
+```
+
+## Next Steps After Creating a Project
+
+```bash
+# Navigate to your project
+cd my-project
+
+# Install dependencies
+npm install  # or yarn, pnpm, bun
+
+# Start the LangGraph development server
+npx @langchain/langgraph-cli@latest dev
+```
+
+The development server provides:
+
+- A local API server for your agents
+- Hot reloading during development
+- Built-in debugging tools
+
+## Analytics
+
+This CLI collects anonymous usage analytics to help improve the tool. The following information is collected:
+
+- Operating system and version
+- Node.js version
+- CLI version
+- Command executed
+
+**No personal information, project details, or code is ever collected.**
+
+To opt out of analytics, set the environment variable:
+
+```bash
+export LANGGRAPH_CLI_NO_ANALYTICS=1
+```
+
+## Requirements
+
+- Node.js 18 or later
+- npm, yarn, pnpm, or bun
+
+## Related Packages
+
+- [@langchain/langgraph](https://www.npmjs.com/package/@langchain/langgraph) — The core LangGraph library
+- [@langchain/langgraph-cli](https://www.npmjs.com/package/@langchain/langgraph-cli) — CLI tools for running LangGraph projects
+
+## License
+
+MIT © [LangChain](https://langchain.com)

libs/create-langgraph/package.json

@@ -3,8 +3,9 @@
   "version": "1.0.0",
   "description": "Create a new LangGraph project",
   "license": "MIT",
-  "main": "dist/index.mjs",
-  "bin": "dist/cli.mjs",
+  "main": "dist/index.js",
+  "bin": "dist/cli.js",
+  "type": "module",
   "files": [
     "dist"
   ],
@@ -20,6 +21,8 @@
     "build": "yarn turbo:command build:internal --filter=create-langgraph",
     "build:internal": "yarn clean && yarn tsc --outDir dist",
     "prepublish": "yarn build",
+    "test": "vitest run",
+    "test:watch": "vitest",
     "format": "prettier --write .",
     "format:check": "prettier --check ."
   },
@@ -36,12 +39,12 @@
     "prettier": "^2.8.3",
     "tsx": "^4.19.3",
     "typescript": "^4.9.5 || ^5.4.5",
-    "vitest": "^3.2.4"
+    "vitest": "^4.0.16"
   },
   "exports": {
     ".": {
-      "types": "./dist/index.d.mts",
-      "default": "./dist/index.mjs"
+      "types": "./dist/index.d.ts",
+      "default": "./dist/index.js"
     }
   },
   "keywords": []

libs/create-langgraph/src/cli.mts

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+#!/usr/bin/env node
+import { Command } from "@commander-js/extra-typings";
+
+import { version } from "./utils/version.js";
+import { withAnalytics } from "./utils/analytics.js";
+import { createNew } from "./index.js";
+import { generateConfig } from "./config.js";
+
+const program = new Command()
+  .name("create-langgraph")
+  .version(version)
+  .description("Create a new LangGraph project");
+
+// Default command: create a new project
+program
+  .argument("[path]", "Path to create the project")
+  .option("-t, --template <template>", "Template to use", "")
+  .hook("preAction", withAnalytics())
+  .action((path, options) => {
+    createNew(path, options.template).catch((error) => {
+      console.error("Error:", error.message);
+      process.exit(1);
+    });
+  });
+
+// Config subcommand: generate langgraph.json
+program
+  .command("config")
+  .description(
+    "Generate a langgraph.json configuration file by scanning for agents"
+  )
+  .argument(
+    "[path]",
+    "Path to the project to scan (defaults to current directory)"
+  )
+  .hook("preAction", withAnalytics())
+  .action((path) => {
+    generateConfig(path).catch((error) => {
+      console.error("Error:", error.message);
+      process.exit(1);
+    });
+  });
+
+program.parse();