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 earns an extra point by reinforcing the free-prose nature of 'need' and enumerating the kind of constraints to embed in it (self-hosted, API, free plan, budget, who will use it). It also clarifies how returned requirement states should be interpreted, which frames what a well-formed input looks like.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.