Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100% for the single 'code' parameter, and the schema already tells the agent where the code comes from (create_plan or list_plans). The description's 'by its code' adds no syntax, format, or validation detail beyond the schema, so the baseline 3 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.