Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100% for the single parameter (pdf_url), which already includes a detailed description ('다운로드 가능한 https URL (허용 형식: application/pdf) (최대 25MB)'). The description only reinforces the PDF-only constraint and the conversion behavior, adding no new parameter-specific semantics, so the baseline of 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.