Level 315 min

LangChain Integration

Use 402bazaar.com services as LangChain tools. Agents discover, evaluate, and pay for the best service automatically.

Create a 402bazaar.com tool

Wrap the x402 payment flow in a LangChain-compatible tool.

TypeScript

import { Tool } from "langchain/tools";

class BazaarTool extends Tool {
  name = "bazaar_call";
  description = "Call a paid API via x402. Input: slug and optional body.";

  async _call(input: string) {
    const { slug, body } = JSON.parse(input);
    const res = await x402Fetch(`/api/v1/proxy/${slug}`, {
      method: "POST",
      body: JSON.stringify(body)
    });
    return JSON.stringify(await res.json());
  }
}

Add discovery tool

Let your agent search the marketplace to find the right service for any task.

TypeScript

class BazaarDiscoverTool extends Tool {
  name = "bazaar_discover";
  description = "Search 402bazaar.com marketplace. Input: search query.";

  async _call(query: string) {
    const res = await fetch(
      `/api/v1/discover?q=${encodeURIComponent(query)}`
    );
    const { services } = await res.json();
    return JSON.stringify(services.slice(0, 5));
  }
}

Use in an agent chain

Combine discovery + execution in an agent that autonomously finds and pays for services.

TypeScript

import { initializeAgentExecutorWithOptions } from "langchain/agents";

const tools = [new BazaarDiscoverTool(), new BazaarTool()];
const agent = await initializeAgentExecutorWithOptions(tools, llm, {
  agentType: "openai-functions",
});

const result = await agent.invoke({
  input: "Find and call a weather service for NYC"
});

Other Frameworks

Claude MCP Integration

Add 402bazaar.com as an MCP server so Claude can discover, compare, and pay for services autonomously.

OpenAI Function Calling

Use x402 services as OpenAI function calls. Your GPT agent discovers and pays for APIs on the fly.

Custom Agent Integration

Build x402 support into any agent framework. Raw HTTP, full control, no dependencies.