A transaction input that is observed but not spent. Reference inputs let a Plutus validator look at the current state of another UTxO (an oracle's latest price, a registry entry, a DAO configuration) and use it during validation, without taking that UTxO out of circulation for other concurrent transactions.
Introduced alongside reference scripts in the Vasil hard fork via CIP-31, reference inputs are how Cardano dApps share live on-chain state at scale without serialising every read.
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- Smart ContractSelf-executing code stored on a blockchain that automatically enforces and executes agreement terms when predefined conditions are met.View term
- eUTXOCardano's extension of the UTXO accounting model; each output can carry datum and script logic, so smart contracts express rules without the shared mutable state used by account-based chains.View term
- OracleA trusted feed that brings off-chain information onto the blockchain so smart contracts can react to it.View term
- DatumA piece of data attached to a UTxO that a smart contract can read when deciding whether the UTxO can be spent.View term
- VasilThe hard fork on September 22, 2022 that improved smart contract efficiency and network performance.View term
- Reference ScriptA Plutus script attached once to a UTxO and then referenced (not re-included) by later transactions that need it, whether to spend a script-locked output, run a minting policy, or validate a withdrawal or certificate.View term