Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100%, so baseline is 3. The description adds context by enumerating valid 'days' values (1, 7, 14, 30, 90, 180, 365) which reinforces the schema's vague '1 | 7 | ...' list. It doesn't add format/syntax details for 'id' or 'vs' beyond schema, but the schema already covers these with examples.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.