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

# CDP Facilitator

Verifying and settling x402 payments yourself means validating signatures, interacting with
blockchains, screening transactions, and managing settlement gas. The CDP Facilitator handles
that work as a hosted service: it validates signed payments, screens transactions, submits
settlement onchain, and reports the result to your resource server.

## Why use the CDP Facilitator

* **Proven at scale.** The CDP Facilitator has processed more than 100 million transactions
  and \$28 million in payment volume across Base and Solana alone.
* **Built-in screening.** OFAC and Know Your Transaction (KYT) checks identify and decline payments involving sanctioned or high-risk addresses.
* **Move from testnet to mainnet with one provider.** Build and test against the same service
  you use in production.
* **Reach buyers across EVM and Solana.** Accept ERC-20 tokens on supported EVM networks and
  SPL tokens on Solana.
* **Charge however you price.** Fixed-price, usage-based, and batched payments through the `exact`,
  `upto`, and `batch-settlement` schemes. All three run on the EVM networks, and Solana
  supports `exact`.
* **Get indexed on the Bazaar.** Your path to joining the most comprehensive marketplace for x402 endpoints.
* **Free to start, inexpensive to scale.** The first 1,000 onchain Facilitator transactions each
  month are free, then each additional onchain transaction costs \$0.001.

## Pricing

CDP charges only after the monthly free tier:

| Tier        | Monthly onchain transactions | Cost per onchain transaction |
| ----------- | ---------------------------- | ---------------------------- |
| Free        | Up to 1,000                  | \$0.00                       |
| Usage-based | Above 1,000                  | \$0.001                      |

Facilitator fees are based on onchain activity, not payment requests. Payment verification is
always free.

With `exact` and `upto`, each accepted payment settles in one onchain transaction. With
`batch-settlement`, vouchers are verified offchain for free and claimed together, so one
onchain transaction can process thousands of payments. Other channel operations, including
deposits, refunds, and withdrawals, each count as one onchain transaction.

This lets high-volume sellers spread settlement costs across thousands of requests instead of
paying a Facilitator fee per request.

## Connect your server

The CDP Facilitator authenticates with your CDP API key ID and secret.

* **TypeScript with the CDP SDK.** `createX402Server` connects to the CDP Facilitator by
  default.
* **TypeScript with the x402 Foundation SDKs.** See
  [Use CDP with an existing x402 server](/x402/seller/production-configuration#use-cdp-with-an-existing-x402-server)
  for adding `createCdpFacilitatorClient` to an existing setup.
* **Python with the x402 Foundation SDK.** Use the CDP SDK's
  [`cdp.x402`](https://github.com/coinbase/cdp-sdk/tree/main/python/cdp/x402) module to create
  an authenticated facilitator configuration for `HTTPFacilitatorClient`.
* **Direct REST access.** Integrate with the
  [verify and settle APIs](/api-reference/v2/rest-api/x402-facilitator/x402-facilitator).

## Advanced

<AccordionGroup>
  <Accordion title="Supported networks, tokens, and schemes">
    The CDP Facilitator supports all ERC-20 tokens on its EVM networks through EIP-3009 or
    Permit2, and SPL tokens on Solana. The following table shows x402 v2 support:

    | Network       | CAIP-2 identifier                         | Schemes                             |
    | ------------- | ----------------------------------------- | ----------------------------------- |
    | Base          | `eip155:8453`                             | `exact`, `upto`, `batch-settlement` |
    | Base Sepolia  | `eip155:84532`                            | `exact`, `upto`, `batch-settlement` |
    | Polygon       | `eip155:137`                              | `exact`, `upto`, `batch-settlement` |
    | Arbitrum      | `eip155:42161`                            | `exact`, `upto`, `batch-settlement` |
    | World         | `eip155:480`                              | `exact`, `upto`, `batch-settlement` |
    | World Sepolia | `eip155:4801`                             | `exact`, `upto`, `batch-settlement` |
    | Solana        | `solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp` | `exact`                             |
    | Solana Devnet | `solana:EtWTRABZaYq6iMfeYKouRu166VU2xqa1` | `exact`                             |

    Support can change as new networks and schemes are added. Use the
    [supported payment schemes and networks endpoint](/api-reference/v2/rest-api/x402-facilitator/get-supported-payment-schemes-and-networks)
    as the programmatic source of truth.
  </Accordion>

  <Accordion title="Supported extensions">
    * **[EIP-2612 gas sponsorship](https://docs.x402.org/extensions/eip2612-gas-sponsoring).**
      Sponsors the initial Permit2 approval for tokens that support EIP-2612, so buyers do not
      need native gas for the approval transaction.
    * **[Bazaar discovery](/x402/seller/get-discovered).** Powers the Bazaar discovery service. After
      the facilitator settles a payment for an endpoint that advertises Bazaar metadata, it
      indexes the endpoint so buyers and agents can find it.
    * **[Builder Code attribution](https://docs.base.org/apps/builder-codes/builder-codes).**
      Supports the `builder-code` extension on EVM settlements. The Facilitator combines the
      application code, client or intermediary codes, and its own facilitator code, then appends
      them to settlement calldata using ERC-8021 Schema 2. Configure attribution in the
      [seller](/x402/seller/production-configuration#add-onchain-attribution) or
      [buyer](/x402/buyer/client-configuration#add-onchain-attribution) guide.
  </Accordion>
</AccordionGroup>

## What to read next

Make your paid endpoints available to buyers and agents by
[listing them in the Bazaar](/x402/seller/get-discovered). For common questions about x402 and the
CDP Facilitator, see the [FAQ](/x402/support/faq).