Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so every parameter is already documented in the schema, and the description largely restates them (id reads one, from/to form a window). It adds only the ordering consequence of from plus the 'from = today lists upcoming' interpretation, so baseline 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.