20 tools with complete input schemas and descriptions present, but quality is inconsistent. Descriptions are in Korean and vary from 20-80 chars (below the 50-200 char baseline for LLM optimization). All tools have proper JSON Schema with typed parameters. However, parameter descriptions are minimal (often just restating the parameter name in Korean), and output schemas are entirely undocumented. No error handling guidance, no recovery hints, and no indication of which tools are idempotent or have side effects. Tool naming follows verb_noun pattern well (capture_screenshot, get_coordinates, click_on), but composition issues exist: wait_and_click combines two concerns; mark_region is a utility rather than a primary action. No tool annotations (readOnlyHint/destructiveHint) despite clear risk classifications in the metadata. Vision-based tools (get_coordinates, check_condition, read_text) depend on external LLM calls but lack documentation of failure modes or fallback behavior.

• Document output schemas for all tools. For vision tools (get_coordinates, get_bounding_box, find_all_elements), specify: {"type": "object", "properties": {"x": {"type": "number"}, "y": {"type": "number"}, ...}, "required": [...]}. For check_condition, specify boolean return. For read_text, specify string return.
• Add tool annotations to all tool definitions. Use readOnlyHint=true for capture_screenshot, get_coordinates, check_condition, read_text, find_all_elements, extract_structured_data, get_clipboard, wait_until. Use destructiveHint=true for click_on, hover_on, drag_from_to, wait_and_click, type_text, press, hotkey, scroll, open_app, open_uri, mark_region.
• Expand parameter descriptions to 50-200 characters. Example: 'image_path' → 'Path to screenshot PNG file (e.g., /tmp/screenshot.png). File must exist and be readable. If missing, returns error: file not found.'
• Add error handling guidance to vision tools. Document: 'If element not found, returns error with available alternatives. Retry with more specific description or call capture_screenshot to verify current state.'
• Split wait_and_click into separate wait_until and click_on tools, or document when to use wait_and_click vs. calling them sequentially. Add idempotentHint=true to tools that are safe to retry (capture_screenshot, get_coordinates, check_condition, read_text, find_all_elements, extract_structured_data, get_clipboard, wait_until).