The LINE Bot MCP Server defines 13 tools with generally clear naming (verb_noun pattern: push_, broadcast_, get_, delete_, set_, cancel_, create_). Tool descriptions are present and moderately detailed (80-200 chars typical), addressing WHAT the tool does and broad use cases. However, schemas show significant gaps: most complex tools (push_flex_message, broadcast_flex_message, create_rich_menu) have incomplete input schema documentation, parameter descriptions are minimal or absent for nested structures. Error handling is basic (createErrorResponse/createSuccessResponse utility exists but no recovery guidance visible). Security is adequate (secrets injected via env vars, no creds in params), but permission checks and audit trails are not visible. Output schemas are not documented. The server follows the verb_noun naming convention well, but lacks the precision required for A-grade quality (detailed param constraints, format specifications, actionable error messages, documented output schemas).

• Document every output schema. For each tool, add a 'Returns' section specifying field names, types, and whether results are paginated. E.g., get_profile returns {userId: string, displayName: string, pictureUrl: string | null, statusMessage: string, language: string}.
• Expand parameter descriptions for nested objects. For push_flex_message and broadcast_flex_message, detail the bubble/carousel structure: 'A flex message object. For bubble format: {type: "bubble", body: {...}, footer?: {...}}. For carousel: {type: "carousel", contents: [bubble, ...]}. See LINE Messaging API docs for full schema.'
• Add error recovery guidance. Wrap error responses with actionable hints: 'Failed to delete rich menu: menu does not exist. Call get_rich_menu_list() to see available menus.' or 'User not found, is DESTINATION_USER_ID set?'
• Document action structure for create_rich_menu. Specify that 'actions' is an array of {type: 'uri' | 'message' | 'postback', label: string, ...} with examples for each type.
• Add permission/scope declarations. For each tool, document required permissions: 'Requires: broadcast_message' for broadcast_*, 'Requires: manage_richmenu' for create_/delete_rich_menu, etc.
• Clarify pagination limits. For get_rich_menu_list and get_follower_ids, state: 'Returns max 100 items per call. Use start (continuation token) to fetch next page. Iterate until start is null or undefined.'
• Implement confirmation for destructive operations. Add an optional 'confirm: true' parameter to delete_rich_menu, cancel_rich_menu_default, and broadcast_* tools, or provide separate 'draft_broadcast' tool that returns a message preview requiring explicit 'send_broadcast_confirmed' call.