OpenPayment Skill

Creates x402 stablecoin payment links via the openpayment CLI.

All links are hosted at OpenPayment and settle in USDC on Base.

Use this skill whenever a user wants to create a payment link, request a stablecoin payment, set up a crypto payment, generate a USDC payment URL, or mentions x402, OpenPayment, or wants to get paid in crypto/stablecoins on Base. Trigger even if the user says things like "create a payment link", "I want to accept USDC", "generate a crypto payment request", "send me money in stablecoins", or "set up a blockchain payment".

About OpenPayment

OpenPayment lets merchants, creators, developers, and AI agents accept USDC payments with shareable payment links and APIs. 0% platform fees, instant settlement to recipient wallet, and no sign-up required. Powered by x402.

Install

npm i -g openpayment

Core Command

openpayment create \
  --type "<PAYMENT_TYPE>" \
  --price "<AMOUNT>" \
  --payTo "<EVM_ADDRESS>" \
  --network "<NETWORK>" \
  [--resourceUrl "<HTTPS_URL_FOR_PROXY>"] \
  --description "<DESCRIPTION>"

Required Flags

Flag	Description	Example
`--type`	Payment type (see below)	`SINGLE_USE`
`--price`	Amount in human-readable USDC	`10` or `0.001`
`--payTo`	Recipient EVM wallet address	`0x1234...abcd`
`--network`	CAIP-2 network identifier	`eip155:8453`

Optional Flags

Flag	Description
`--description`	Payment description (max 500 chars)
`--resourceUrl`	Required when `--type` is `PROXY`; upstream API URL (`https://...`)
`--json`	Output as JSON instead of plain text

Payment Types

Type	When to use
`SINGLE_USE`	One-time payment with fixed price (e.g., a specific order, invoice)
`MULTI_USE`	Fixed price, can be paid multiple times (e.g., recurring product)
`VARIABLE`	Reusable link; payer chooses amount per payment (e.g., tips, donations)
`PROXY`	Fixed-price multi-use payment that calls a private upstream API after successful settlement

Default to SINGLE_USE unless the user specifies otherwise.

Networks

Network	Flag value	Description
Base Mainnet	`eip155:8453`	Production, real USDC
Base Sepolia	`eip155:84532`	Testnet, test USDC

Default to eip155:8453 (Base Mainnet) unless the user says "test", "testnet", or "sepolia".

Support for other networks will be added soon.

Currency

The default currency is USDC.

Base Mainnet USDC: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
Base Sepolia USDC: 0x036CbD53842c5426634e7929541eC2318f3dCF7e

Support for other stablecoins and custom ERC-20 tokens will be added soon.

Example Commands

Basic single-use payment link (10 USDC on Base)

openpayment create \
  --type "SINGLE_USE" \
  --price "10" \
  --payTo "0xYourWalletAddress" \
  --network "eip155:8453" \
  --description "Payment for order #123"

Crowdfund / donation (multi-use, suggest 1 USDC, user can change)

openpayment create \
  --type "VARIABLE" \
  --price "1" \
  --payTo "0xYourWalletAddress" \
  --network "eip155:8453" \
  --description "Support my work"

Recurring subscription (multi-use, fixed price)

openpayment create \
  --type "MULTI_USE" \
  --price "9.99" \
  --payTo "0xYourWalletAddress" \
  --network "eip155:8453" \
  --description "Monthly subscription"

Proxy payment link

openpayment create \
  --type "PROXY" \
  --price "10" \
  --payTo "0xYourWalletAddress" \
  --network "eip155:8453" \
  --resourceUrl "https://private-api.example.com/endpoint" \
  --description "Proxy payment"

Testnet payment link

openpayment create \
  --type "SINGLE_USE" \
  --price "5" \
  --payTo "0xYourWalletAddress" \
  --network "eip155:84532" \
  --description "Test payment"

JSON output (for scripting)

openpayment create \
  --type "SINGLE_USE" \
  --price "25" \
  --payTo "0xYourWalletAddress" \
  --network "eip155:8453" \
  --json

Output

Plain text:

Payment created successfully
paymentId: <paymentId>
url: <paymentUrl>

Example:

Payment created successfully
paymentId: ed5b8e83-607b-4853-90c6-f4f3ba821424
url: https://openpayment.link/pay/?paymentId=ed5b8e83-607b-4853-90c6-f4f3ba821424

JSON (--json):

{
  "paymentId": "<paymentId>",
  "url": "<paymentUrl>"
}

Example:

{
  "paymentId": "ed5b8e83-607b-4853-90c6-f4f3ba821424",
  "url": "https://openpayment.link/pay/?paymentId=ed5b8e83-607b-4853-90c6-f4f3ba821424"
}

Workflow for Handling User Requests

The first time the skill runs, explain to the user what payment types and networks are allowed.

Identify missing info you need: amount (--price), receiver wallet address (--payTo). If --type=PROXY, also require --resourceUrl.
Infer defaults: type defaults to SINGLE_USE, network defaults to eip155:8453 (Base Mainnet).
Confirm info with the user before creating.
Run the command using the bash tool.
Present the payment URL clearly to the user so they can share it.

What to ask if info is missing

No wallet address: "What's the recipient EVM wallet address (starting with 0x)?"
No amount: "How much USDC should the payment be for?"
No type specified but context suggests multi-use: "Should this link be single-use (one payment only) or reusable?", "Should the amount be fixed or editable?"
No network specified: assume Base Mainnet; mention it in your response.
PROXY without upstream URL: "Please provide the private upstream API URL for this proxy payment (--resourceUrl)."

Validation Rules (enforced by CLI before any API call)

--type: must be SINGLE_USE, MULTI_USE, VARIABLE, or PROXY
--price: positive decimal number (e.g. 0.001, 10, 99.99)
--payTo: valid EVM address — 0x followed by 40 hex characters
--network: must be eip155:8453 or eip155:84532
--description: optional string, max 500 characters
--resourceUrl: required only for PROXY; must be a valid https:// URL

Security Notes

Never ask for or share user private keys and secrets.

Learn More

Website: https://openpayment.link
GitHub: https://github.com/noncept/openpayment

openpayment

Safety Notice

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