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 extra semantics beyond the schema: it reiterates the requirement to pass both aweme_id and comment_id together, explains when to reuse IDs from first-level results, and forbids passing reply-level comment_ids. This additional guidance, especially the exclusion, elevates it above the schema baseline.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.