FHE Encrypted Inputs

Use this skill when building or reviewing the path encrypted data takes from a user's browser into an onchain contract. This is the entry point for all user-supplied confidential values in FHEVM, and the proof binding is what prevents replay and injection attacks.

When To Use

• Implementing a contract function that accepts encrypted user input
• Building frontend code that encrypts values before submitting transactions
• Reviewing input validation and proof verification in contract entry points
• Debugging "invalid proof" or "wrong sender" reverts on encrypted input submission
• Designing contract interfaces that accept both external and onchain encrypted values

Core Mental Model

When a user input must stay confidential, the user does not send plaintext to the chain. They encrypt the value client-side using the Zama SDK, producing a ciphertext and a cryptographic proof. The proof binds the ciphertext to a specific sender address AND a specific contract