27 tools with consistent naming (pdf_* prefix) and complete input schemas. Descriptions present but generic (avg ~60 chars, below 194-char baseline). All parameters have type definitions and descriptions. No output schemas documented. Error handling minimal, no recovery guidance or actionable error messages. Missing tool annotations (readOnlyHint/destructiveHint). Composition is sound (single responsibility per tool), but parameter descriptions lack format/constraint details (e.g., 'page' lacks bounds, 'angle' lacks enum constraint). No secrets exposed. Moderate quality, functional but not LLM-optimized.

• Add output schemas to all 27 tools. Document return types as JSON Schema (e.g., pdf_info returns {page_count: integer, version: string, encrypted: boolean, metadata: object}).
• Expand descriptions to 100-200 chars. Include WHEN to call and WHAT happens. E.g., 'Close an open PDF document and release memory. Call after extracting text to free resources. Returns success or error if doc_id not found.'
• Add tool annotations: mark pdf_delete_pages, pdf_merge, pdf_repair, pdf_rotate_pages, pdf_compress, pdf_set_metadata, pdf_add_watermark with destructiveHint=true. Mark all read-only tools with readOnlyHint=true.
• Constrain numeric/enum parameters. Add 'enum: [90, 180, 270]' to angle; add 'minimum: 1' to page; add 'enum: [low, medium, high]' to quality. Document in descriptions: 'Rotation angle in degrees: 90, 180, or 270 only.'
• Add error recovery guidance. E.g., pdf_open: 'If file not found, call pdf_list(directory) to discover available PDFs.' pdf_search_text: 'If no results, try pdf_extract_text() to inspect full content.'