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Get Started Free →View, create, cancel, bid, and claim Aavegotchi GBM auctions on Base mainnet (8453). Subgraph-first discovery (Goldsky), with onchain verification + execution via Foundry cast. Safety-first: DRY_RUN defaults to 1 (simulate with cast call; only broadcast with cast send when DRY_RUN=0 and explicitly instructed).
| Test case | Without → With | Effect | Δ tokens | Δ turns |
|---|---|---|---|---|
| case-07 | ✗→✓ | ▲ Improved | 118% | 0% |
| case-01 | ✗→✓ | ▲ Improved | 159% | 0% |
| case-09 | ✗→✓ | ▲ Improved | 337% | 0% |
| case-12 | ✗→✓ | ▲ Improved | 287% | 0% |
| case-13 | ✗→✓ | ▲ Improved | 176% | 0% |
DRY_RUN=1. Never broadcast unless explicitly instructed.~/.foundry/bin/cast chain-id --rpc-url "${BASE_MAINNET_RPC:-https://mainnet.base.org}" must be 8453.~/.foundry/bin/cast wallet address --private-key "$PRIVATE_KEY" must equal $FROM_ADDRESS.highestBid matches the highestBid you pass into commitBid / swapAndCommitBid.$PRIVATE_KEY.This skill includes shell commands. Treat any value you copy from a user or an external source (subgraph responses, chat messages, etc.) as untrusted.
Rules:
eval, bash -c, sh -c).0x + 40 hex chars."<AUCTION_ID>" to avoid accidental shell interpolation. Replace them with literal values only after validation.Quick validators (replace the placeholder values):
bashpython3 - <<'PY' import re auction_id = "<AUCTION_ID>" # digits only token_contract = "<TOKEN_CONTRACT_ADDRESS>" # 0x + 40 hex chars token_id = "<TOKEN_ID>" # digits only amount = "<TOKEN_AMOUNT>" # digits only if not re.fullmatch(r"[0-9]+", auction_id): raise SystemExit("AUCTION_ID must be base-10 digits only") if not re.fullmatch(r"0x[a-fA-F0-9]{40}", token_contract): raise SystemExit("TOKEN_CONTRACT_ADDRESS must be a 0x + 40-hex address") if not re.fullmatch(r"[0-9]+", token_id): raise SystemExit("TOKEN_ID must be base-10 digits only") if not re.fullmatch(r"[0-9]+", amount): raise SystemExit("TOKEN_AMOUNT must be base-10 digits only") print("ok") PY
Required env vars:
PRIVATE_KEY: EOA private key used for cast send (never print/log).FROM_ADDRESS: EOA address that owns NFTs and will submit txs.BASE_MAINNET_RPC: RPC URL. If unset, use https://mainnet.base.org.GBM_SUBGRAPH_URL: Goldsky subgraph endpoint for auctions.Optional env vars:
DRY_RUN: 1 (default) to only simulate via cast call. Set to 0 to broadcast via cast send.RECIPIENT_ADDRESS: for swap flows; receives any excess GHST refunded by the contract. Defaults to FROM_ADDRESS.GOLDSKY_API_KEY: optional; if set, include Authorization: Bearer ... header in subgraph calls.SLIPPAGE_PCT: defaults to 1 (%); used in swapAmount estimate math.GHST_USD_PRICE, ETH_USD_PRICE: optional overrides; if unset, fetch from CoinGecko in the swap math snippets.Recommended defaults (override via env if needed):
bashexport BASE_MAINNET_RPC="${BASE_MAINNET_RPC:-https://mainnet.base.org}" export GBM_DIAMOND="${GBM_DIAMOND:-0x80320A0000C7A6a34086E2ACAD6915Ff57FfDA31}" export GHST="${GHST:-0xcD2F22236DD9Dfe2356D7C543161D4d260FD9BcB}" export USDC="${USDC:-0x833589fCD6eDb6E08f4c7C32D4f71b54BDA02913}" export GBM_SUBGRAPH_URL="${GBM_SUBGRAPH_URL:-https://api.goldsky.com/api/public/project_cmh3flagm0001r4p25foufjtt/subgraphs/aavegotchi-gbm-baazaar-base/prod/gn}" export DRY_RUN="${DRY_RUN:-1}" export SLIPPAGE_PCT="${SLIPPAGE_PCT:-1}"
Notes:
~/.foundry/bin/cast so they work in cron/non-interactive shells.See references/subgraph.md for canonical queries.
Auction by id (quick):
bashcurl -s "$GBM_SUBGRAPH_URL" -H 'content-type: application/json' ${GOLDSKY_API_KEY:+-H "Authorization: Bearer $GOLDSKY_API_KEY"} --data '{ "query":"query($id:ID!){ auction(id:$id){ id type contractAddress tokenId quantity seller highestBid highestBidder totalBids startsAt endsAt claimAt claimed cancelled presetId category buyNowPrice startBidPrice } }", "variables":{"id":"<AUCTION_ID>"} }'
Active auctions (ends soonest first):
bashNOW=$(date +%s) curl -s "$GBM_SUBGRAPH_URL" -H 'content-type: application/json' ${GOLDSKY_API_KEY:+-H "Authorization: Bearer $GOLDSKY_API_KEY"} --data "{ \"query\":\"query(\$now:BigInt!){ auctions(first:20, orderBy: endsAt, orderDirection: asc, where:{claimed:false, cancelled:false, startsAt_lte:\$now, endsAt_gt:\$now}){ id type contractAddress tokenId quantity highestBid highestBidder totalBids startsAt endsAt claimAt presetId category seller } }\", \"variables\":{\"now\":\"$NOW\"} }"
The onchain source of truth is the GBM diamond.
Confirm core auction fields (full struct decode):
bash~/.foundry/bin/cast call "$GBM_DIAMOND" \ 'getAuctionInfo(uint256)((address,uint96,address,uint88,uint88,bool,bool,address,(uint80,uint80,uint56,uint8,bytes4,uint256,uint96,uint96),(uint64,uint64,uint64,uint64,uint256),uint96,uint96))' \ "<AUCTION_ID>" \ --rpc-url "$BASE_MAINNET_RPC"
Useful individual getters:
bash~/.foundry/bin/cast call "$GBM_DIAMOND" 'getAuctionHighestBid(uint256)(uint256)' "<AUCTION_ID>" --rpc-url "$BASE_MAINNET_RPC" ~/.foundry/bin/cast call "$GBM_DIAMOND" 'getAuctionHighestBidder(uint256)(address)' "<AUCTION_ID>" --rpc-url "$BASE_MAINNET_RPC" ~/.foundry/bin/cast call "$GBM_DIAMOND" 'getAuctionStartTime(uint256)(uint256)' "<AUCTION_ID>" --rpc-url "$BASE_MAINNET_RPC" ~/.foundry/bin/cast call "$GBM_DIAMOND" 'getAuctionEndTime(uint256)(uint256)' "<AUCTION_ID>" --rpc-url "$BASE_MAINNET_RPC" ~/.foundry/bin/cast call "$GBM_DIAMOND" 'getContractAddress(uint256)(address)' "<AUCTION_ID>" --rpc-url "$BASE_MAINNET_RPC" ~/.foundry/bin/cast call "$GBM_DIAMOND" 'getTokenId(uint256)(uint256)' "<AUCTION_ID>" --rpc-url "$BASE_MAINNET_RPC" ~/.foundry/bin/cast call "$GBM_DIAMOND" 'getTokenKind(uint256)(bytes4)' "<AUCTION_ID>" --rpc-url "$BASE_MAINNET_RPC"
Onchain method:
createAuction((uint80,uint80,uint56,uint8,bytes4,uint256,uint96,uint96),address,uint256)(uint256)High-level steps:
ContractNotAllowed).setApprovalForAll(GBM_DIAMOND,true)InitiatorInfo:startTime must be in the future.endTime - startTime must be between 3600 and 604800 seconds (1h to 7d).tokenKind is 0x73ad2146 (ERC721) or 0x973bb640 (ERC1155).buyItNowPrice optional; startingBid optional (if nonzero, you must approve GHST for the 4% prepaid fee).cast call using --from "$FROM_ADDRESS".cast send only when explicitly instructed (DRY_RUN=0).(contractAddress, tokenId).Simulate create (ERC721 example):
bash~/.foundry/bin/cast call "$GBM_DIAMOND" \ 'createAuction((uint80,uint80,uint56,uint8,bytes4,uint256,uint96,uint96),address,uint256)(uint256)' \ "(<START_TIME>,<END_TIME>,1,<CATEGORY>,0x73ad2146,<TOKEN_ID>,<BUY_NOW_GHST_WEI>,<STARTING_BID_GHST_WEI>)" \ "<ERC721_CONTRACT_ADDRESS>" "<PRESET_ID>" \ --from "$FROM_ADDRESS" \ --rpc-url "$BASE_MAINNET_RPC"
Broadcast create (only when explicitly instructed):
bash~/.foundry/bin/cast send "$GBM_DIAMOND" \ 'createAuction((uint80,uint80,uint56,uint8,bytes4,uint256,uint96,uint96),address,uint256)(uint256)' \ "(<START_TIME>,<END_TIME>,1,<CATEGORY>,0x73ad2146,<TOKEN_ID>,<BUY_NOW_GHST_WEI>,<STARTING_BID_GHST_WEI>)" \ "<ERC721_CONTRACT_ADDRESS>" "<PRESET_ID>" \ --private-key "$PRIVATE_KEY" \ --rpc-url "$BASE_MAINNET_RPC"
Post-create (find your newest auctions and confirm):
bashcurl -s "$GBM_SUBGRAPH_URL" -H 'content-type: application/json' ${GOLDSKY_API_KEY:+-H "Authorization: Bearer $GOLDSKY_API_KEY"} --data '{ "query":"query($seller:Bytes!){ auctions(first:10, orderBy: createdAt, orderDirection: desc, where:{seller:$seller}){ id type contractAddress tokenId quantity createdAt startsAt endsAt claimed cancelled } }", "variables":{"seller":"<FROM_ADDRESS_LOWERCASE>"} }'
Onchain method:
cancelAuction(uint256)Steps:
claimed, cancelled, endsAt, highestBid.getAuctionInfo(auctionId) to verify ownership and state.cast call (--from "$FROM_ADDRESS").Simulate:
bash~/.foundry/bin/cast call "$GBM_DIAMOND" 'cancelAuction(uint256)' "<AUCTION_ID>" \ --from "$FROM_ADDRESS" \ --rpc-url "$BASE_MAINNET_RPC"
Broadcast (only when explicitly instructed):
bash~/.foundry/bin/cast send "$GBM_DIAMOND" 'cancelAuction(uint256)' "<AUCTION_ID>" \ --private-key "$PRIVATE_KEY" \ --rpc-url "$BASE_MAINNET_RPC"
Onchain method:
commitBid(uint256,uint256,uint256,address,uint256,uint256,bytes) (last bytes is ignored; pass 0x)Steps:
highestBid and token params; you must pass the exact current onchain highestBid or it reverts UnmatchedHighestBid.references/bid-math.md (uses onchain bidDecimals + stepMin).bidAmount.cast call (optional but recommended).Simulate:
bash~/.foundry/bin/cast call "$GBM_DIAMOND" \ 'commitBid(uint256,uint256,uint256,address,uint256,uint256,bytes)' \ "<AUCTION_ID>" "<BID_AMOUNT_GHST_WEI>" "<HIGHEST_BID_GHST_WEI>" "<TOKEN_CONTRACT_ADDRESS>" "<TOKEN_ID>" "<TOKEN_AMOUNT>" 0x \ --from "$FROM_ADDRESS" \ --rpc-url "$BASE_MAINNET_RPC"
Broadcast (only when explicitly instructed):
bash~/.foundry/bin/cast send "$GBM_DIAMOND" \ 'commitBid(uint256,uint256,uint256,address,uint256,uint256,bytes)' \ "<AUCTION_ID>" "<BID_AMOUNT_GHST_WEI>" "<HIGHEST_BID_GHST_WEI>" "<TOKEN_CONTRACT_ADDRESS>" "<TOKEN_ID>" "<TOKEN_AMOUNT>" 0x \ --private-key "$PRIVATE_KEY" \ --rpc-url "$BASE_MAINNET_RPC"
Onchain method:
swapAndCommitBid((address,uint256,uint256,uint256,address,uint256,uint256,uint256,address,uint256,uint256,bytes))Struct fields (in order):
tokenIn (USDC)swapAmount (USDC 6dp)minGhstOut (GHST wei; must be >= bidAmount)swapDeadline (unix; must be <= now + 86400)recipient (refund receiver for excess GHST)auctionIDbidAmount (GHST wei)highestBid (must match onchain)tokenContracttokenIDamount (tokenAmount/quantity)_signature (ignored; pass 0x)Compute swapAmount estimate in references/swap-math.md.
Simulate:
bash~/.foundry/bin/cast call "$GBM_DIAMOND" \ 'swapAndCommitBid((address,uint256,uint256,uint256,address,uint256,uint256,uint256,address,uint256,uint256,bytes))' \ "($USDC,<SWAP_AMOUNT_USDC_6DP>,<MIN_GHST_OUT_GHST_WEI>,<SWAP_DEADLINE_UNIX>,${RECIPIENT_ADDRESS:-$FROM_ADDRESS},<AUCTION_ID>,<BID_AMOUNT_GHST_WEI>,<HIGHEST_BID_GHST_WEI>,<TOKEN_CONTRACT_ADDRESS>,<TOKEN_ID>,<TOKEN_AMOUNT>,0x)" \ --from "$FROM_ADDRESS" \ --rpc-url "$BASE_MAINNET_RPC"
Broadcast (only when explicitly instructed):
bash~/.foundry/bin/cast send "$GBM_DIAMOND" \ 'swapAndCommitBid((address,uint256,uint256,uint256,address,uint256,uint256,uint256,address,uint256,uint256,bytes))' \ "($USDC,<SWAP_AMOUNT_USDC_6DP>,<MIN_GHST_OUT_GHST_WEI>,<SWAP_DEADLINE_UNIX>,${RECIPIENT_ADDRESS:-$FROM_ADDRESS},<AUCTION_ID>,<BID_AMOUNT_GHST_WEI>,<HIGHEST_BID_GHST_WEI>,<TOKEN_CONTRACT_ADDRESS>,<TOKEN_ID>,<TOKEN_AMOUNT>,0x)" \ --private-key "$PRIVATE_KEY" \ --rpc-url "$BASE_MAINNET_RPC"
Same method as above, but:
tokenIn = 0x0000000000000000000000000000000000000000--value <SWAP_AMOUNT_WEI> must equal the swapAmount you pass inside the tuple.Broadcast (only when explicitly instructed):
bash~/.foundry/bin/cast send "$GBM_DIAMOND" \ 'swapAndCommitBid((address,uint256,uint256,uint256,address,uint256,uint256,uint256,address,uint256,uint256,bytes))' \ "(0x0000000000000000000000000000000000000000,<SWAP_AMOUNT_WEI>,<MIN_GHST_OUT_GHST_WEI>,<SWAP_DEADLINE_UNIX>,${RECIPIENT_ADDRESS:-$FROM_ADDRESS},<AUCTION_ID>,<BID_AMOUNT_GHST_WEI>,<HIGHEST_BID_GHST_WEI>,<TOKEN_CONTRACT_ADDRESS>,<TOKEN_ID>,<TOKEN_AMOUNT>,0x)" \ --value "<SWAP_AMOUNT_WEI>" \ --private-key "$PRIVATE_KEY" \ --rpc-url "$BASE_MAINNET_RPC"
Onchain methods:
claim(uint256)batchClaim(uint256[])Claim readiness:
now >= endsAt.now >= endsAt + cancellationTime.cancellationTime is readable from storage slot 12 (see references/recipes.md).claimAt (if populated), but always verify onchain.Simulate:
bash~/.foundry/bin/cast call "$GBM_DIAMOND" 'claim(uint256)' "<AUCTION_ID>" \ --from "$FROM_ADDRESS" \ --rpc-url "$BASE_MAINNET_RPC"
Broadcast (only when explicitly instructed):
bash~/.foundry/bin/cast send "$GBM_DIAMOND" 'claim(uint256)' "<AUCTION_ID>" \ --private-key "$PRIVATE_KEY" \ --rpc-url "$BASE_MAINNET_RPC"
Onchain methods:
buyNow(uint256)swapAndBuyNow((address,uint256,uint256,uint256,address,uint256))These are not required for the primary use case, but are adjacent to bidding flows. If you use them, follow the same safety gating:
cast call)auction, auctions, bid, bids):bashcurl -s "$GBM_SUBGRAPH_URL" -H 'content-type: application/json' ${GOLDSKY_API_KEY:+-H "Authorization: Bearer $GOLDSKY_API_KEY"} --data '{ "query":"{ __schema { queryType { fields { name } } } }" }' \ | python3 -c 'import json,sys; f=[x[\"name\"] for x in json.load(sys.stdin)[\"data\"][\"__schema\"][\"queryType\"][\"fields\"]]; print([n for n in f if n in (\"auction\",\"auctions\",\"bid\",\"bids\")])'
bashcurl -s "$GBM_SUBGRAPH_URL" -H 'content-type: application/json' ${GOLDSKY_API_KEY:+-H "Authorization: Bearer $GOLDSKY_API_KEY"} --data '{\"query\":\"query($id:ID!){ auction(id:$id){ id contractAddress tokenId } }\",\"variables\":{\"id\":\"0\"}}'
bash~/.foundry/bin/cast call "$GBM_DIAMOND" \ 'getAuctionInfo(uint256)((address,uint96,address,uint88,uint88,bool,bool,address,(uint80,uint80,uint56,uint8,bytes4,uint256,uint96,uint96),(uint64,uint64,uint64,uint64,uint256),uint96,uint96))' \ 0 \ --rpc-url "$BASE_MAINNET_RPC"
UnmatchedHighestBid: you passed a stale highestBid param. Refetch onchain and retry.InvalidAuctionParams: token contract / id / amount mismatch. Refetch and verify.AuctionNotStarted / AuctionEnded: timing mismatch. Check startsAt/endsAt (subgraph + onchain).AuctionClaimed: already claimed or cancelled. Check claimed (subgraph + onchain).BiddingNotAllowed: diamond paused, contract bidding disabled, or re-entrancy lock. Refetch onchain state.LibTokenSwap: swapAmount must be > 0LibTokenSwap: deadline expiredLibTokenSwap: Insufficient output amount (increase swapAmount or slippage)Other measured skills in the registry, with their headline benchmark lift.