The term used for a legal action challenging the enforceability of a contract is:

Rescission refers to the legal action taken to cancel a contract and restore the parties to their original positions prior to the contract's creation. This term is particularly relevant when one party believes the contract should not be enforceable due to reasons such as misrepresentation, fraud, undue influence, or incapacity. By seeking rescission, a party is challenging the validity of the contract itself, arguing that it should not be upheld by law.

In contrast, specific performance relates to a legal remedy where a court orders a party to perform their obligations under a contract rather than simply compensating the other party with damages. Mutual consent pertains to an agreement where both parties willingly agree to the terms, and discharge typically refers to the termination of contractual obligations. These terms do not encapsulate the notion of challenging a contract’s enforceability as effectively as rescission does.