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Brian

Get started

@brian-ai/langchain is a powerful SDK that simplifies the process of building powerful Langchain web3 agents that can interact with the blockchain using their wallet.

Install the package

bun
bun i @brian-ai/langchain

Set environment file

Create a .env file adding the following environment variables:

# .env
BRIAN_API_KEY="brian_api_key"
AGENT_PRIVATE_KEY="0xprivatekey"
OPENAI_PRIVATE_KEY="openai_api_key"

Add langchain packages

bun
bun i @langchain/core @langchain/openai

Create your first agent

Create a new file under src/index.ts and add the following code:

import { createBrianAgent } from "@brian-ai/langchain";
import { ChatOpenAI } from "@langchain/openai";
 
const main = async () => {
  const agent = await createBrianAgent({
    apiKey: process.env.BRIAN_API_KEY!,
    privateKeyOrAccount: process.env.AGENT_PRIVATE_KEY! as `0x${string}`,
    llm: new ChatOpenAI(),
  });
 
  // Execute blockchain operations using natural language
  const result = await agent.invoke({
    input: "Swap 1 USDC for ETH on Ethereum",
  });
  console.log(result);
};
 
main();

Run the agent

In the example we're using bun to run the project. You can also compile it to js and run it using node.

bun src/index.ts