cross-nft
A Claude Code skill that drives the CROSS NFT marketplace at https://www.crossnft.io — list, browse, buy, make/cancel/accept offers — using the same backends the live site does.
- Stack: EOA + viem + raw HTTPS (no browser automation, no ERC-4337)
- Backends:
api.crossnft.io/graphql — Apollo GraphQL indexer (collections, tokens, listings, offers, activities, stats, search)MarketplaceV1 at 0x0df40a50f2c09885c18245dc90e8e9dcd0e4c3bc on CROSS Chain (chain id 612055)
- Default payment token: MGold (
MGT, decimals 18) at 0x5b1579a758916560f00212b78a7af728eaa0ffa9
- Subcommands:
- read:
collections, token, tokens, listing, offer-onchain, offers, activities, stats, search
- write:
list, cancel-listing, buy, offer, cancel-offer, accept-offer
- Distribution: standalone Claude skill and wrapped as a Claude Code plugin
v0.1 ships read + write. Each write script auto-detects the right approval flow:
list / accept-offer — runs setApprovalForAll(marketplace, true) on the NFT contract if not already approved.buy / offer — for ERC-20 paymentToken, runs approve(marketplace, total) (exact amount, or unlimited with --max-approve); for native paymentToken (sentinel 0x0…0), attaches msg.value instead.
Install — Standalone
Option 1 — Plain skill (one user, fastest)
git clone <this-repo> /tmp/skill-cross-nft
bash /tmp/skill-cross-nft/install.sh # symlinks into ~/.claude/skills/
Or manually:
cp -r skills/cross-nft ~/.claude/skills/
cd ~/.claude/skills/cross-nft && npm install
Option 2 — Claude Code plugin (marketplace-installable)
{
"name": "cross-nft",
"source": { "source": "github", "repo": "to-nexus/skill-cross-nft" },
"category": "blockchain"
}
Configuration
Read-path commands (collections, token, tokens, listing, offer-onchain, offers, activities, stats, search) do not require a private key. Only the write commands need one.
cp skills/cross-nft/.env.example skills/cross-nft/.env
chmod 600 skills/cross-nft/.env
| Variable | Required | Default | Notes |
|---|
PRIVATE_KEY | only for write commands | — | EOA signer, 0x + 64 hex chars |
WALLET_ADDRESS | optional | derived from PK | Mismatch warns via signerWarn |
CROSS_RPC_URL | optional | https://mainnet.crosstoken.io:22001/ | Override only if you have a private RPC |
MAX_TRADE_NOTIONAL | recommended | unset | Per-trade cap (payment-token units); aborts above this |
CONFIRM_THRESHOLD | recommended | 1 | Trades above this notional require --confirm |
MIN_GAS_NATIVE | optional | 0.001 | Source-chain native (CROSS) floor |
MARKETPLACE_ADDRESS | optional | 0x0df40a50f2c09885c18245dc90e8e9dcd0e4c3bc | Debug override only |
CROSSNFT_API_BASE | optional | https://api.crossnft.io | Debug override only |
Quick start
Inside Claude Code, just describe the action in plain language. The skill activates on phrases like:
Direct CLI:
cd ~/.claude/skills/cross-nft
# read
node scripts/collections.mjs --days 7d --top 10
node scripts/token.mjs 0xa3bd4e86cd0ec20b03c9710359599c9f82f8fe9e 30164746843126
node scripts/listing.mjs 321699
node scripts/offers.mjs --collection 0xa3bd4e86cd0ec20b03c9710359599c9f82f8fe9e --top 5
node scripts/activities.mjs --collection 0xa3bd4e86cd0ec20b03c9710359599c9f82f8fe9e --types SALE --top 5
node scripts/search.mjs "primal heroz"
# write (PRIVATE_KEY required)
PRIVATE_KEY=0x... node scripts/list.mjs 0xa3bd…fe9e 30164746843126 30 --confirm
PRIVATE_KEY=0x... node scripts/buy.mjs 321699 --confirm
PRIVATE_KEY=0x... node scripts/offer.mjs 0xa3bd…fe9e 30164746843126 25 --duration 604800 --confirm
PRIVATE_KEY=0x... node scripts/cancel-listing.mjs 321699
PRIVATE_KEY=0x... node scripts/accept-offer.mjs 30 --confirm
All commands emit a single JSON object on stdout.
Layout
