Catches pyproject.toml metadata that breaks your next release: end-of-life requires-python, PEP 639 licence drift, classifier conflicts, setuptools too old for SPDX. Date-aware, offline. Runs entirely in your browser — nothing is uploaded.
Free here: Every finding for the pyproject.toml open in your editor, with the line, the spec that changed and the replacement text. In the editor: Sweeping every pyproject.toml in a monorepo in one pass and writing a dated report file you keep in the repo — that part asks for a licence key.
Same engine as the VS Code extension, byte for byte.