Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 0% and both parameters are bare strings, but the description does supply the otherwise-missing enumeration of valid scheme values (base64, base64url, hex, url, rot13), which is real added value. The text parameter still gets no semantics beyond its name, so it only partially compensates.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.