Independent Researcher Independent Researcher The Witnessed Execution Protocol (WEXP) defines a record format and a verification procedure for classifying the strength of execution- related evidence about actions performed by software and AI systems. A WEXP record asserts, for a single action, a Witnessability Level (WL) bounded by the execution-relevant boundary that the witness controls. WEXP grades only the evidentiary strength of an execution claim; it does not certify the action's correctness, safety, or alignment. This document specifies WEXP Core: the record model, required fields, the two classification axes (Witnessability Level and Conformance Class), the honesty invariants that bound claims, the verifier procedure, and failure semantics. WEXP Core is profile- independent and validates standalone.