agent402-openai-tools

Drop-in OpenAI function-calling tools for Agent402 — the open-source, self-hostable x402 + MCP server with ~1,100 pay-per-call web tools (browser, web search, PDF, images, live data, payment helpers, wallet-keyed memory).

• Zero new infra. Get back a ready-to-pass tools array for chat.completions, Assistants v2, or the Responses API.
• Free tier by default. No wallet needed — the compute-payable tools settle with a built-in proof-of-work (sub-second sha256 puzzle).
• Wallet-only tools optional. Pass an @x402/fetch-wrapped fetch and the model can call any tool in the catalog.
• Doesn't burn discovery tokens. Stop the model from "exploring" the web to find a tool — give it the catalog up front.

Install

npm install openai agent402-openai-tools

Use with chat.completions

import OpenAI from "openai";
import { agent402Tools } from "agent402-openai-tools";

const openai = new OpenAI();

// Pick the tools you want the model to know about. Smaller list = better tool-selection.
const { tools, execute } = await agent402Tools({ slugs: ["extract", "hash", "render", "screenshot"] });

const res = await openai.chat.completions.create({
  model: "gpt-4o-mini",
  messages: [{ role: "user", content: "Get the title of https://example.com/article" }],
  tools,
});

// Resolve tool calls (free — paid via proof-of-work behind the scenes).
const call = res.choices[0].message.tool_calls?.[0];
if (call) {
  const result = await execute(call.function.name, JSON.parse(call.function.arguments));
  console.log(result);
}

Use with Assistants v2 or the Responses API

The shape returned by agent402Tools() is the same OpenAI function-calling JSON used by every flavor of the OpenAI API. Pass tools directly to assistants.create({ tools }) or to responses.create({ tools }).

Pay with USDC (wallet-only tools)

For the catalog's wallet-only tools (browser, network, memory), wrap your fetch with @x402/fetch and pass it in:

import { wrapFetchWithPayment } from "@x402/fetch";
import { x402Client } from "@x402/core/client";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.AGENT_KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const { tools, execute } = await agent402Tools({
  freeOnly: false,
  fetch: payFetch,
});

Self-hosted Agent402

Point at your own instance:

const { tools, execute } = await agent402Tools({ baseUrl: "https://agent402.example.com" });

Trust & baseUrl

The catalog server you point baseUrl at controls the name, description, and JSON Schema of every generated tool — and tool descriptions are passed to your LLM. Only point baseUrl at an Agent402 instance you operate or trust. The default (https://agent402.tools) is the maintained, open-source hosted instance.

License

MIT