@phan-forbid-undeclared-magic-properties

The @phan-forbid-undeclared-magic-properties tag forbids accessing undeclared magic properties on the class it decorates, so only the properties actually documented via @property may be accessed.

Parsing a @phan-forbid-undeclared-magic-properties tag produces a PhanForbidUndeclaredMagicPropertiesTag instance. Being a pure marker, it adds nothing beyond the $name and optional $description every Tag already carries.

See Phan's Annotating Your Source Code wiki, where it is mentioned in body text.