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Description
PHP Semver Checker has one https://github.com/tomzx/php-semver-checker/blob/master/docs/Ruleset.md and is pretty handy for quickly checking before making a change.
In most cases where there is already a version constraint set it is very inconvenient to have to make the change, then run the tool, then have to rollback parts of the work done to avoid breaking changes.
The ruleset could be a simple md file referencing the original ruleset, specifying the few overrides and explaining all the custom Magento 2 rules being added