> ## Documentation Index
> Fetch the complete documentation index at: https://hedera-0c6e0218-docs--429.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Quickstart (JavaScript)

> Get started with the Hedera Agent Kit using JavaScript/TypeScript

## Quickstart - Create a Hedera Agent

See the npm package: [https://www.npmjs.com/package/hedera-agent-kit](https://www.npmjs.com/package/hedera-agent-kit)

### 1. Create your project directory

```bash theme={null}
mkdir hello-hedera-agent-kit
cd hello-hedera-agent-kit
```

### 2. Install the agent kit and init the project

Init and install with npm:

```bash theme={null}
npm init -y
```

Open `package.json` and add `"type": "module"` to enable ES modules.

```bash theme={null}
npm install hedera-agent-kit @langchain/core langchain @langchain/langgraph @hashgraph/sdk dotenv
```

> **Note**: The Hedera Agent Kit supports both **LangChain v1** (recommended) and **LangChain classic** (v0.3, legacy). The examples below use LangChain v1.

### 3. Install ONE of these AI provider packages

```bash theme={null}
# Option 1: OpenAI (requires API key)
# for Langchain classic
npm install @langchain/openai@^0.6

# for LangChain v1
npm install @langchain/openai@^1npm install @langchain/openai@^0.6

# Option 2: Anthropic Claude (requires API key)
# for LangChain classic
npm install @langchain/anthropic@^0.3

# for LangChain v1
npm install @langchain/anthropic@^1

# Option 3: Groq (free tier available)
# for Langchain classic
npm install @langchain/groq@^0.2

# for LangChain v1
npm install @langchain/groq@^1

# Option 4: Ollama (100% free, runs locally)
# for Langchain classic
npm install @langchain/ollama@^0.2

# for LangChain v1
npm install @langchain/ollama@^1
```

### 4. Add Environment Variables

Create a `.env` file in your directory:

```bash theme={null}
touch .env
```

If you don't already have a Hedera account, create a testnet account at [https://portal.hedera.com/dashboard](https://portal.hedera.com/dashboard)

Add the following to the `.env` file:

```env theme={null}
# Required: Hedera credentials (get free testnet account at https://portal.hedera.com/dashboard)
ACCOUNT_ID="0.0.xxxxx"
PRIVATE_KEY="0x..." # ECDSA encoded private key

# Optional: Add the API key for your chosen AI provider
OPENAI_API_KEY="sk-proj-..."      # For OpenAI (https://platform.openai.com/api-keys)
ANTHROPIC_API_KEY="sk-ant-..."    # For Claude (https://console.anthropic.com)
GROQ_API_KEY="gsk_..."            # For Groq free tier (https://console.groq.com/keys)
# Ollama doesn't need an API key (runs locally)
```

### 5. Create your agent

Once you have your project set up, create an `index.js` file:

```bash theme={null}
touch index.js
```

```javascript index.js theme={null}
// index.js
import { Client, PrivateKey } from '@hashgraph/sdk';
import { HederaLangchainToolkit, AgentMode } from 'hedera-agent-kit';
import { createAgent } from 'langchain';
import { MemorySaver } from '@langchain/langgraph';
import { ChatOpenAI } from '@langchain/openai';
// import { ChatAnthropic } from '@langchain/anthropic';
// import { ChatGroq } from '@langchain/groq';
// import { ChatOllama } from '@langchain/ollama';
import dotenv from 'dotenv';

dotenv.config();

async function main() {
  // Hedera client setup (Testnet by default)
  const client = Client.forTestnet().setOperator(
    process.env.ACCOUNT_ID,
    PrivateKey.fromStringECDSA(process.env.PRIVATE_KEY)
  );

  // Prepare Hedera toolkit
  const hederaAgentToolkit = new HederaLangchainToolkit({
    client,
    configuration: {
      tools: [], // Add specific tools here if needed, or leave empty for defaults/plugins
      plugins: [], // Add plugins here
      context: {
        mode: AgentMode.AUTONOMOUS,
      },
    },
  });

  // Fetch tools from a toolkit
  const tools = hederaAgentToolkit.getTools();

  const llm = new ChatOpenAI({
    model: 'gpt-4o-mini',
    apiKey: process.env.OPENAI_API_KEY,
  });

  // const llm = new ChatAnthropic({
  //   model: 'claude-sonnet-4-5-20250929',
  //   apiKey: process.env.ANTHROPIC_API_KEY,
  // });

  // const llm = new ChatGroq({
  //   model: 'llama-3.3-70b-versatile',
  //   apiKey: process.env.GROQ_API_KEY,
  // });
  
  // const llm = new ChatOllama({
  //   model: 'llama3.1',
  //   baseUrl: process.env.OLLAMA_BASE_URL || 'http://127.0.0.1:11434',
  // });

  const agent = createAgent({
    model: llm,
    tools: tools,
    systemPrompt: 'You are a helpful assistant with access to Hedera blockchain tools',
    checkpointer: new MemorySaver(),
  });

  console.log('Sending a message to the agent...');
  
  const response = await agent.invoke(
    { messages: [{ role: 'user', content: "what's my balance?" }] },
    { configurable: { thread_id: '1' } }
  );

  console.log(response.messages[response.messages.length - 1].content);
}

main().catch(console.error);
```

> **Using a different AI provider?** You can substitute `ChatOpenAI` with other LangChain chat models like `ChatAnthropic`, `ChatGroq`, or `ChatOllama`. Install the corresponding package (e.g., `@langchain/anthropic`) and update the import accordingly.

### 6. Run Your "Hello Hedera Agent Kit" Example

From the root directory, run your example agent:

```bash theme={null}
node index.js
```

***

## Examples

Clone the repository and try out different example agents. Both **LangChain v1** (recommended) and **LangChain classic** (v0.3) examples are available.

See the full [Developer Examples](https://github.com/hashgraph/hedera-agent-kit-js/blob/main/docs/DEVEXAMPLES.md) documentation for detailed setup instructions.

**Available Examples:**

* **Option A** - [Tool Calling Agent](https://github.com/hashgraph/hedera-agent-kit-js/blob/main/docs/DEVEXAMPLES.md#option-a-run-the-example-tool-calling-agent): Simple tasks with Hedera tools in autonomous mode
* **Option B** - [Structured Chat Agent](https://github.com/hashgraph/hedera-agent-kit-js/blob/main/docs/DEVEXAMPLES.md#option-b-run-the-structured-chat-agent-langchain-v03-only): Complex multistep tasks (LangChain v0.3 only)
* **Option C** - [Human in the Loop Agent](https://github.com/hashgraph/hedera-agent-kit-js/blob/main/docs/DEVEXAMPLES.md#option-c-try-the-human-in-the-loop-chat-agent): Controlled workflow with RETURN\_BYTES mode
* **Option D** - [MCP Server](https://github.com/hashgraph/hedera-agent-kit-js/blob/main/docs/DEVEXAMPLES.md#option-d-try-out-the-mcp-server): Interact with Hedera via Claude Desktop or IDEs like Cursor
* **Option E** - [ElizaOS Agent](https://github.com/hashgraph/hedera-agent-kit-js/blob/main/docs/DEVEXAMPLES.md#option-e-try-out-the-hedera-agent-kit-with-elizaos): Build autonomous AI agents with ElizaOS framework

***

## Agent Execution Modes

This tool has two execution modes with AI agents:

| Mode                     | Description                                                         |
| ------------------------ | ------------------------------------------------------------------- |
| `AgentMode.AUTONOMOUS`   | The transaction is executed autonomously using the operator account |
| `AgentMode.RETURN_BYTES` | The transaction bytes are returned for the user to sign and execute |

***

## Resources

* **GitHub**: [https://github.com/hashgraph/hedera-agent-kit-js](https://github.com/hashgraph/hedera-agent-kit-js)
* **npm**: [hedera-agent-kit](https://www.npmjs.com/package/hedera-agent-kit)
* **Issues**: [https://github.com/hashgraph/hedera-agent-kit-js/issues](https://github.com/hashgraph/hedera-agent-kit-js/issues)
* **Developer Examples**: [DEVEXAMPLES.md](https://github.com/hashgraph/hedera-agent-kit-js/blob/main/docs/DEVEXAMPLES.md)