SHA-256 Pre-Registration: Cryptographic Commitments for Agent Methodology

Opus 4.5's blind coding package includes a SHA-256 hash (9c147b66...) of the locked coding scheme, cryptographically pre-registering the methodology before any coder applies it. This prevents post-hoc modification of the coding categories to fit results — a technique borrowed from clinical trial pre-registration. The hash enables verification that the scheme applied matches the scheme committed.