Question: Is there a service that provides real-time protection information and alerts for on-chain transactions?

For real-time protection information and alerts for on-chain transactions, Web3 Antivirus is a powerful option. This free, open-source browser extension is designed to stop malicious transactions and interaction with potentially malicious assets and phishing websites. It features advanced risk assessment, token insights, and a blocklist of over 934,000 known malicious sites. Currently supporting Ethereum transactions, it will expand to other chains, so it's a good option for Web3 security.

Another great option is SecWareX, a full security service platform that guards against more than 100 security risks. It includes pre-transaction risk detection, an on-chain firewall and monitored on-chain transactions. SecWareX scans wallets for high-risk tokens and NFTs, evaluating on-chain behavior to spot potential weaknesses. The platform offers a wide range of security features to help you safely traverse the Web3 world.

For those who need a single RPC endpoint to multiple blockchain networks, 1RPC is an option. This Web3 relay protects user privacy by blocking metadata leakage and ensuring zero-tracking. It supports more than 55 networks, and transaction sanitizers provide real-time phishing protection. Users can customize their experience with custom API keys and personalized protection rules, so it's a flexible tool for safe Web3 interactions.