Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100%, so the baseline is 3. The description adds meaning by naming specific summary contents such as ten-year figures and the MR Index, and by describing the fields returned for a register section, including condition, action, timing, cost and cost basis.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.