Looks up SPDX identifiers and common aliases (GPLv3, Apache 2.0, BSD-3, MPL2, CC0) in a local reference of 55 licenses tagged with permissions, conditions and limitations; parses SPDX expressions with AND, OR, WITH and parentheses; identifies a pasted LICENSE file by fingerprint. The policy verdict is by category (permissive, weak copyleft, copyleft, open source, any) and the compatibility column applies documented rules for using a dependency inside your project license — a starting point for review, not legal advice. Everything runs locally.