Paying for Services (x402)

Use the Finance District wallet to access paid API endpoints and gated content via the x402 HTTP payment protocol. The wallet handles payment authorization and signing automatically — the agent fetches the content in a single call.

How x402 Works

x402 is an HTTP-native payment protocol:

1. A server returns HTTP 402 with payment requirements
2. The wallet signs a payment and retries the request with a payment header
3. The facilitator verifies and settles the payment
4. The server returns the content

The Finance District wallet supports x402 payments on multiple chains and assets, not just a single network.

Confirm wallet is authenticated

fdx status

If the wallet is not authenticated, refer to the authenticate skill.

Check Balance

Ensure the wallet has sufficient funds to cover the payment:

fdx call getWalletOverview

Fetching Paid Content

getX402Content — Fetch content from a paid endpoint

The primary command for accessing x402 resources. It discovers payment requirements, authorizes payment, and retrieves the content in one step:

fdx call getX402Content --url <endpoint-url>

Parameters

Parameter	Required	Description
--url	Yes	The x402-enabled endpoint URL
--preferredNetwork	No	Preferred chain ID for payment (e.g. 8453 for Base)
--preferredNetworkName	No	Preferred chain name (e.g. base, ethereum)
--preferredAsset	No	Preferred payment asset (e.g. USDC)
--maxPaymentAmount	No	Maximum payment amount to authorize

authorizePayment — Pre-authorize a payment

For cases where you want to inspect payment requirements or authorize without fetching:

fdx call authorizePayment --url <endpoint-url>

Parameters

Same as getX402Content.

Examples

# Fetch content from a paid API (auto-discovers requirements and pays)
fdx call getX402Content \
  --url https://api.example.com/premium/data

# Prefer paying with USDC on Base
fdx call getX402Content \
  --url https://api.example.com/premium/data \
  --preferredNetworkName base \
  --preferredAsset USDC

# Set a max payment cap
fdx call getX402Content \
  --url https://api.example.com/premium/data \
  --maxPaymentAmount 1000000

# Just authorize without fetching
fdx call authorizePayment \
  --url https://api.example.com/premium/data

Flow

1. Check authentication with fdx status
2. Check wallet balance with fdx call getWalletOverview
3. Call fdx call getX402Content --url <endpoint> to fetch paid content
4. If the payment amount seems high, use fdx call authorizePayment first to inspect, then confirm with the human before proceeding
5. Return the fetched content to the human

Important: Always inform your human about the payment before executing, especially for unfamiliar endpoints or amounts that seem high. Let them confirm they want to proceed.

Difference from Coinbase x402

The Finance District wallet supports multi-chain and multi-asset x402 payments. You can specify a preferred network and asset, giving flexibility to pay from whichever chain and token has available balance. Coinbase's implementation is limited to Base USDC.

Prerequisites

• Must be authenticated (fdx status to check, see authenticate skill)
• Wallet must have sufficient balance in the required payment asset on the required network
• If insufficient funds, suggest using the fund-wallet skill or swap-tokens skill

Error Handling

• "Not authenticated" — Run fdx setup first, or see authenticate skill
• "Insufficient balance" — Check balance; see fund-wallet skill
• "No x402 payment requirements found" — The URL may not be an x402-enabled endpoint
• "Payment failed" — May be a network issue; retry or try a different preferred network