opensea-marketplace

OpenSea Marketplace

Buy and sell NFTs through OpenSea on EVM chains and Solana. Fulfill listings, accept or create offers, cancel orders, make cross-chain purchases, and sweep multiple listings.

When to use this skill (scope_in)

Use opensea-marketplace when you need to execute trades:

• Buy an NFT (fulfill a listing)
• Sell an NFT (accept an offer)
• Create a new Seaport listing or offer
• Create, fulfill, or cancel a Solana order
• Cross-chain NFT purchases (pay with tokens from a different chain)
• Sweep multiple listings in one transaction

When NOT to use this skill (scope_out, handoff)

Need	Use instead
Query collection/NFT data, search, browse listings	opensea-api
Swap ERC20 tokens	opensea-swaps
Set up wallet signing providers	opensea-wallet
Build/register/gate AI agent tools	opensea-tool-sdk

Buying an NFT

1. Find the NFT and check its listing (use opensea-api skill):

   opensea listings best-for-nft cool-cats-nft 1234
   

2. Get the order hash from the response, then get fulfillment data:

   ./scripts/opensea-fulfill-listing.sh ethereum 0x_order_hash 0x_your_wallet
   

3. The response contains transaction data to execute onchain.

ERC20-denominated listings (stablecoins, WETH, etc.)

Some listings are priced in an ERC20 token instead of the native currency (e.g. USDG on robinhood, USDC on base). The fulfillment response looks the same, but two extra steps are required before the transaction will succeed:

1. Read the price using its decimals field. Listing prices are returned as raw base units with an explicit decimals value (e.g. {"currency": "USDG", "decimals": 6, "value": "89000000"} = 89 USDG). Never assume 18 decimals, because stablecoins commonly use 6.
2. Approve the payment token before fulfilling. The fulfillment transaction has value: 0 and the payment is pulled with transferFrom, so the buyer must hold enough of the payment token and have approved the address that pulls it. That address is the Seaport contract in transaction.to when fulfillerConduitKey is bytes32(0), otherwise the conduit returned by getConduit(conduitKey) on the Seaport ConduitController (0x00000000F9490004C11Cef243f5400493c00Ad63). Approve the total of all ERC20 consideration items, fees included. Missing approval or balance is the most common cause of "simulation reverted" on ERC20-priced listings.