Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100%, and parameter descriptions are clear ('Phone number to format', 'Country code (US, UK, DE, FR, etc.)'). The description adds the context of 'country conventions' but does not explain the default country behavior or accepted codes beyond what the schema provides. Baseline score of 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.