NFT Reveal Rarity Checker

WHAT IT DOES

NFT Reveal Rarity Checker is a specialized browser extension that analyzes NFT metadata to determine rarity scores and trait statistics in real-time. When you view an NFT detail page, the tool automatically detects the token contract and ID, then queries the contract's tokenURI() function to fetch the metadata. It extracts all attributes and compares them against the collection's trait rarity statistics—computed from the collection's total supply, trait frequencies, and metadata patterns. The panel displays a comprehensive rarity report including: an overall rarity score from 0-100, a rarity tier (Common, Uncommon, Rare, Epic, Legendary) with color coding, individual trait rarity percentages showing how rare each attribute is within the collection, and a visual representation of the NFT's rarity ranking. The tool automatically refreshes its analysis when you navigate to a new NFT or when a reveal occurs, ensuring you always see the latest rarity data. Optional desktop notifications alert you when an NFT exceeds your configured rarity threshold.

WHERE IT RUNS

This overlay operates on OpenSea asset detail pages. It works in any browser that supports the BotGentz extension framework and has an EVM-compatible wallet extension installed. The panel automatically resets its state when you navigate between different NFT pages, re-fetching metadata and recalculating rarity for each new token.

HOW TO USE

Install the extension and navigate to any NFT detail page on OpenSea. The panel will automatically detect the NFT contract and token ID. Click "Check Rarity" to begin the analysis—the tool will fetch the metadata from the tokenURI, load the collection's trait statistics, and compute the rarity scores. The panel displays the results including the rarity tier, score, and individual trait rarity percentages. Configure your settings: choose your preferred rarity data source (API, on-chain registry, or computed from metadata), set an auto-refresh interval (from manual only to 30 seconds), and define a rarity score threshold for desktop notifications. Click "Copy Results" to copy the rarity summary to your clipboard. The tool automatically refreshes when you navigate to a new NFT, ensuring you always have the most current rarity analysis.

MECHANISM: METADATA-DRIVEN RARITY COMPUTATION WITH MULTI-SOURCE STATISTICS

Unlike generic rarity tools that rely solely on external API dependencies or single data sources, this extension implements a flexible rarity computation engine that supports multiple data sources with automatic fallback. The primary mechanism works by: (1) reading the NFT contract's tokenURI() function via eth_call to obtain the metadata URI, (2) resolving IPFS (ipfs://), Arweave (ar://), and HTTP URIs to fetch the raw metadata JSON, (3) parsing the metadata to extract structured attributes (supports standard OpenSea metadata format, ERC-721 metadata extensions, and custom schemas), and (4) computing rarity scores using trait frequency analysis. The rarity algorithm calculates the frequency of each trait value within the collection by referencing either: (a) an external API endpoint that aggregates collection statistics, (b) an on-chain trait registry contract if deployed, or (c) a computed approximation based on the collection's total supply and trait distribution heuristics. Each trait's rarity is calculated as (100 - trait_frequency_percentage), where trait_frequency_percentage is (trait_count / total_supply) * 100. The overall rarity score is the average of all individual trait rarity scores, weighted by trait significance. The tool then maps the score to a tier: 0-29 = Common (gray), 30-54 = Uncommon (green), 55-74 = Rare (blue), 75-89 = Epic (purple), and 90-100 = Legendary (orange). The computed rarity data is cached per contract address to minimize repeated API calls, with a configurable cache invalidation period. The tool also supports manual refresh and threshold-based desktop notifications using GM_notification when high-rarity NFTs are detected.

THE PANEL

The overlay panel is fully draggable via its title bar and remembers its position per-site using GM_setValue. It snaps to the nearest edge when dragged within 40px of any screen boundary. The panel includes clear sections for NFT details (contract address, token ID, name), configuration (rarity data source dropdown, auto-refresh interval selector, threshold input), rarity result display (tier with color coding, score, trait breakdown), and action buttons (Check Rarity, Copy Results, Reset). The result section shows the rarity tier and score prominently, followed by a scrollable list of traits sorted by rarity descending (most rare first). Each trait displays the trait name, trait value, percentage occurrence, and individual rarity score. Pressing Escape temporarily dismisses the panel until you navigate to a new NFT page or manually reactivate via the extension toolbar button. The panel automatically refreshes its data when you navigate to a new NFT, triggering a new rarity analysis.

PLEASE NOTE

This extension requires the free BotGentz framework extension to be installed and active. You must also have a real EVM-compatible wallet extension (such as MetaMask, WalletConnect, Coinbase Wallet, or Rabby) already installed in your browser—the overlay uses your wallet's RPC provider to make eth_call requests to read the tokenURI and other contract data. This tool works exclusively with Ethereum Virtual Machine chains including Ethereum mainnet, Polygon, Arbitrum, Optimism, and Base. The tool is read-only—no transactions are signed or sent, and no wallet funds are ever accessed. Rarity calculations depend on the availability and accessibility of metadata—some collections may use non-standard metadata formats, custom IPFS gateways, or rate-limited APIs that may affect analysis. The tool cannot compute rarity for collections without accessible token metadata or trait rarity data; cannot guarantee that the fetched metadata is accurate or reflects the final revealed state if the reveal is time-delayed; depends on external metadata APIs or IPFS gateways that may be rate-limited or unavailable; cannot account for trait combinations or subjective rarity beyond statistical trait frequency; and does not support collections that use non-standard metadata formats (e.g., SVG metadata, custom JSON schemas) or contracts that do not implement tokenURI(). No private keys, wallet balances, browsing history, or NFT ownership data are ever collected, transmitted, or stored—all metadata reads and rarity computations are performed locally in your browser.