20 tools with consistent verb_noun naming (pdf_*). All have descriptions (avg ~100 chars, baseline 194). Input schemas present with typed parameters and descriptions. However, output schemas are NOT documented in the source, only inferred from test assertions. Parameter descriptions lack format constraints (e.g., no enum for 'format' in pdf_render_page, no min/max for numeric params like 'dpi', 'page'). Error handling is basic (tool errors reported but no recovery guidance). No tool annotations (readOnlyHint, destructiveHint). Risk classifications visible in metadata but not exposed to LLM. Missing idempotency guarantees and confirmation patterns for destructive ops (delete_pages, decrypt, encrypt).

• Add formal output schemas to all tools. Document return types as JSON Schema (e.g., pdf_info returns {page_count: integer, width: number, height: number, ...}).
• Convert free-form string parameters to JSON Schema enums. For pdf_render_page.format, use {"enum": ["png", "jpeg"]}. For pdf_draw.shape, use {"enum": ["line", "rectangle", "circle", "ellipse"]}.
• Add min/max constraints to numeric parameters. E.g., dpi: {type: integer, minimum: 72, maximum: 600}, page: {type: integer, minimum: 1}, font_size: {type: number, minimum: 1, maximum: 100}.
• Implement confirmation pattern for destructive ops. Add optional 'confirm' boolean param to pdf_delete_pages, pdf_decrypt, pdf_encrypt. When false, return a preview/summary; when true, execute.
• Add tool annotations to schema. Mark pdf_info, pdf_extract_text, pdf_validate, pdf_form_fields with readOnlyHint=true. Mark pdf_delete_pages, pdf_decrypt, pdf_encrypt with destructiveHint=true. Mark idempotent ops (pdf_create, pdf_merge) with idempotentHint=true.