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

# Corbits

> Integrate Corbits facilitator for x402 payment processing

Corbits is a hosted facilitator service that streamlines x402 payment processing. By using Corbits’ endpoints, you can offload payment verification and settlement without needing to operate your own facilitator infrastructure.

## Prerequisites

* Node.js and npm installed
* A SKALE Chain endpoint
* Basic understanding of x402 protocol

## Configuration

### Environment Variables

Create a `.env` file with Corbits configuration:

```bash theme={null}
# Receiver address for the x402 payment
RECEIVING_ADDRESS=0xAddress_Receiving_Payment

# please don't share your private key with anyone
PRIVATE_KEY=0xyour_pk
```

### SDK import

Please install the following Viem and Farmeter SDKs created by the Corbits team:

```bash theme={null}
npm install viem
```

```bash theme={null}
npm install @faremeter/info
```

```bash theme={null}
npm install @faremeter/middleware
```

## Integration with Corbits

<Tabs>
  <Tab title="Server Setup">
    ```typescript theme={null}
    import { serve } from "@hono/node-server";
    import { Hono } from "hono";
    import { hono as middleware } from "@faremeter/middleware";
    import { evm } from "@faremeter/info";
    import "dotenv/config";

    const app = new Hono();

    const receiver_address = process.env.RECEIVING_ADDRESS || "0xsome_default_address";
    const facilitator = "https://facilitator.corbits.dev";

    const paywalledMiddleware = await middleware.createMiddleware({
      facilitatorURL: facilitator,
      accepts: [
        evm.x402Exact({
          network: "eip155:324705682",
          asset: "USDC",
          amount: "1000", // $0.0001 in USDC base units
          payTo: receiver_address,
        }),
      ],
    });

    app.get("/api/free", (c) => {
      return c.json({
        type: "free",
        message: "This is free data that does not require payment",
        timestamp: new Date().toISOString(),
        data: {
          temperature: 72,
          humidity: 45,
          conditions: "Sunny",
        },
      });
    });

    // Premium endpoint with payment required
    app.get("/api/premium", paywalledMiddleware, (c) => {
        return c.json({
        type: "paid",
        message: "This is is a paid data that does require x402 payment",
        timestamp: new Date().toISOString(),
        data: {
          temperature: 72,
          humidity: 45,
          conditions: "Sunny",
        },
      });
    });

    serve(app, (info) => {
      console.log(`Listening on http://localhost:${info.port}`);
    });
    ```
  </Tab>

  <Tab title="Client Setup">
    ```typescript theme={null}
    import { createLocalWallet } from "@faremeter/wallet-evm";
    import { createPaymentHandler } from "@faremeter/payment-evm/exact";
    import { wrap as wrapFetch } from "@faremeter/fetch";
    import {skaleBaseSepoliaTestnet} from "viem/chains";
    import "dotenv/config";

    const pk = process.env.PRIVATE_KEY

    if (!pk) {
      throw new Error("PRIVATE_KEY must be set in your environment");
    }

    const url = `http://localhost:3000/api/premium`;

    const wallet = await createLocalWallet(skaleBaseSepoliaTestnet, pk);

    const fetchWithPayer = wrapFetch(fetch, {
      handlers: [createPaymentHandler(wallet)],
    });

    const response = await fetchWithPayer(url);

    if (response.ok) {
      const data = await response.json();
      console.log("Response data:", data);
    } else {
      console.error(`Error: ${response.statusText}`);
    }
    ```
  </Tab>
</Tabs>

## Troubleshooting

### Connection Issues

If you cannot connect to Corbits:

1. Verify the facilitator URL is correct
2. Check network connectivity
3. Ensure API credentials are valid
4. Review firewall settings

### Payment Failures

Common causes and solutions:

| Issue                 | Solution                                |
| --------------------- | --------------------------------------- |
| Invalid signature     | Verify wallet configuration and signing |
| Insufficient balance  | Ensure payer has enough tokens          |
| Network mismatch      | Check chain ID matches configuration    |
| Expired authorization | Increase `maxTimeoutSeconds`            |

## Resources

* [Corbits Documentation](https://docs.corbits.dev/facilitator/introduction/overview)
* [x402 Protocol Specification](https://x402.org)

***

<Note>
  This entity -- Corbits -- is deployed and activley supporting SKALE. These are 3rd party services that may have their own terms and conditions and privacy polices. Use these services at your own risk. AI and agents is a highly experimental space; the 3rd party software solutions may have bugs or be unaudited. You and your agents and your customers use all 3rd party services chosen at your own risk and per their terms.
</Note>