NFT Listing Expiry Alert

WHAT IT DOES

NFT Listing Expiry Alert watches the current page for NFT listings, reads the listing expiry times from the marketplace contract via eth_call, and triggers alerts when listings are about to expire (with configurable warning windows), helping users track when they need to relist or take action. It ensures you never miss an expiry and can relist your NFTs at the right time.

WHERE IT RUNS

This tool operates as a userscript within the BotGentz extension framework, running directly in your browser on any website. It works on any EVM-compatible blockchain page—Ethereum, Polygon, Arbitrum, Optimism, and more—where NFT marketplaces with listing expiry are used. The tool integrates seamlessly into your workflow, appearing as a draggable panel that stays accessible as you manage your NFT listings.

HOW TO USE

Enter the marketplace contract address and the token IDs you want to monitor in the "Listing Setup" section (comma-separated). Specify the expiry function name (e.g., "getListingExpiry", "listingExpiry"). Choose your warning window (30 minutes, 1 hour, 6 hours, 12 hours, or 24 hours before expiry). Set the refresh interval and toggle desktop notifications on or off. Click "Connect & Monitor Listings" to connect your real wallet extension, which will begin checking listing expiry times at your specified interval. The panel displays each token ID with its time remaining or expiry status. You'll receive notifications when listings are about to expire. Use "Check Now" for an immediate check, or "Stop Monitoring" to disconnect.

TECHNICAL OPERATION

NFT Listing Expiry Alert uses raw JSON-RPC calls via window.ethereum.request() to interact with the blockchain. It loads ethers at runtime using a simple script tag injection for ABI encoding and contract interactions. The tool reads listing expiry times using eth_call with the user-specified expiry function. It attempts multiple common function names (getListingExpiry, listingExpiry, getExpiry, expiryTime) as fallbacks. The tool calculates the time remaining by comparing the expiry timestamp with the current block timestamp (or system time). It checks the user-defined warning window and triggers notifications when the time remaining falls below the threshold. The tool tracks alerted listings to avoid duplicate notifications. The display shows the time remaining in a human-readable format with color-coded status indicators.

THE PANEL

The NFT Listing Expiry Alert panel is fully draggable and remembers its position between sessions using GM_setValue. It snaps to the edge of the viewport for a clean interface and can be collapsed to a small icon when not in use. The panel is resizable to accommodate longer content. Press Escape to quickly close or collapse the panel. The design is optimized for productivity with a dark theme, clear visual hierarchy, and responsive controls that adapt to your workflow.

PLEASE NOTE

This tool requires the free BotGentz extension installed in your browser and a real EVM wallet extension (MetaMask, Rabby, etc.) already installed. EVM chains only—this does not work on non-EVM blockchains. The tool cannot read listing expiry times if the marketplace does not expose a view function for them, cannot detect off-chain listings, cannot automatically relist expired NFTs, and cannot predict if the listing will be extended. No private keys are stored or transmitted—all data is read-only from the blockchain. Always verify the marketplace contract address and expiry function before starting monitoring.