> ## Documentation Index
> Fetch the complete documentation index at: https://docs.abs.xyz/llms.txt
> Use this file to discover all available pages before exploring further.

# Accept x402 Payments

> Add x402 payment middleware to your server so agents and applications can pay for API access on Abstract.

This guide walks through adding x402 payment middleware to your server so clients must pay to access your endpoints.

<Accordion title="Prerequisites">
  * A wallet address to receive payments
  * An existing HTTP API built with Express, Next.js, Hono, Gin, FastAPI, or Flask
  * Node.js 18+, Go 1.21+, or Python 3.10+
</Accordion>

## 1. Install dependencies

<Tabs>
  <Tab title="Express">
    ```bash theme={null}
    npm install @x402/express @x402/core @x402/evm
    ```
  </Tab>

  <Tab title="Next.js">
    ```bash theme={null}
    npm install @x402/next @x402/core @x402/evm
    ```
  </Tab>

  <Tab title="Hono">
    ```bash theme={null}
    npm install @x402/hono @x402/core @x402/evm
    ```
  </Tab>

  <Tab title="Go">
    ```bash theme={null}
    go get github.com/coinbase/x402/go
    ```
  </Tab>

  <Tab title="Python">
    ```bash theme={null}
    pip install x402
    ```
  </Tab>
</Tabs>

## 2. Add payment middleware

Wrap your paid routes with x402 middleware and point it at the Abstract facilitator.

```typescript theme={null}
import express from "express";
import { paymentMiddleware, x402ResourceServer } from "@x402/express";
import { ExactEvmScheme } from "@x402/evm/exact/server";
import { HTTPFacilitatorClient } from "@x402/core/server";

const app = express();
const payTo = "0xYourWalletAddress";

const facilitatorClient = new HTTPFacilitatorClient({
  url: "https://facilitator.x402.abs.xyz",
});

app.use(
  paymentMiddleware(
    {
      "GET /weather": {
        accepts: [
          {
            scheme: "exact",
            price: "$0.001",
            network: "eip155:2741",
            payTo,
          },
        ],
        description: "Weather data",
        mimeType: "application/json",
      },
    },
    new x402ResourceServer(facilitatorClient).register(
      "eip155:*",
      new ExactEvmScheme()
    ),
  ),
);

app.get("/weather", (_req, res) => {
  res.send({ weather: "sunny", temperature: 70 });
});
```

## 3. Shape the paid resource

For agent-facing APIs, define:

* a stable route
* a clear description
* a deterministic response format
* a price that is cheap enough for repeated automated use

## 4. Test the flow

The protected route should:

1. return `402 Payment Required` when called without payment
2. advertise the payment requirements in the response
3. return `200` once the client retries with a valid payment

## Next

* Continue to [`Make x402 Payments`](/ai-agents/payments/x402/making-payments) to test a paying client
* Compare with [`MPP`](/ai-agents/payments/mpp/overview) if you expect repeated micro-payments