The server has 17 tools, all with explicit registration via @app.tool() decorators and present descriptions. However, significant quality gaps reduce the score: (1) Most parameter descriptions lack detail about constraints, formats, and usage context. (2) Output schemas are entirely undocumented, tools return strings but no structured field definitions are provided. (3) Error handling is minimal; tools don't guide recovery or categorize failures. (4) Several tools combine related concerns (e.g., multiple coordinate systems for tap/swipe create cognitive overhead rather than clear single responsibility). (5) Tool names are generally clear (e.g., ios_select_device_by_udid), but descriptions are brief and lack context about when to use each variant. Baseline: 549 production tools average 194 chars per description; these average ~120 chars. Parameters lack type suffixes (e.g., 'udid' vs 'device_udid') which would disambiguate IDs from names.

• Define formal output schemas for all tools. ios_list_devices should return {devices: [{udid: string, name: string, state: string}]} not a freeform string. ios_screenshot should return {base64: string, format: string, width: int, height: int}.
• Convert button and key code values to JSON Schema enums. ios_tap_button parameter 'button' should use enum: [APPLE_PAY, HOME, LOCK, POWER, SIDE_BUTTON, SIRI] instead of documenting in description.
• Add range constraints to numeric parameters. ios_tap_with_viewport_coordinates should document: 'x: integer (0 to screen_width), y: integer (0 to screen_height)' and duration_in_milliseconds: integer (1-10000).
• Consolidate coordinate system variants. Replace ios_tap_with_viewport_coordinates + ios_tap_with_screen_coordinates with single ios_tap(x, y, coordinate_system: enum[viewport|screen], duration_in_milliseconds).
• Document state prerequisites and error conditions. E.g., ios_type_text should state: 'Requires a text field to be focused. Returns error if no device is selected or device is not responding.'
• Add recovery guidance to error scenarios. E.g., 'If ios_select_device_by_name fails, call ios_list_devices to see available device names.'
• Enhance description brevity for discovery. Average description is ~120 chars; increase to 150-200 chars (baseline 194) with context on when/why to call each tool.
• Add dependency hints. ios_tap_button description should state: 'Call after ios_get_selected_device to verify a device is active, or after ios_boot_device if the device is not yet running.'