BCCF Kernel is a boundary‑constrained causal evaluation engine that enforces primitive constraints (P0–P5) at the earliest stage of proposal evaluation. It provides a structured pipeline for validatingartifacts (bridges/claims), computing sustainability ratios (Π), and surfacing failure signatures with actionable feedback. This release includes the core kernel, primitive‑first constraint layer, and multidomain validation datasets and tests (fusion, galaxy dynamics, and chemistry). It also ships chemistry observation tables and a flammability mix matrix, enabling reproducible Π‑based evaluation and prediction workflows across domains.