Critical gaps across all dimensions. Tool definitions lack input schemas entirely, no visible JSON Schema definitions in source code. Descriptions are minimal (10-50 chars) and generic. Parameters are undocumented. No output schemas defined. Error handling is absent. The server registers 12 tools but provides almost no machine-readable guidance for LLM selection or parameter construction. This is a skeleton implementation missing the substance required for agent integration.

• Add complete JSON Schema input definitions to all 12 tools. Each parameter must have type, description, and constraints (enum, min/max, pattern). Example: { type: 'object', properties: { mailbox_id: { type: 'string', description: 'The mailbox ID returned by mail_list_mailboxes' }, limit: { type: 'integer', minimum: 1, maximum: 100, description: 'Number of messages to return (default 20)' } }, required: ['mailbox_id'] }
• Expand all tool descriptions to 100-200 characters. Include WHAT the tool does, WHEN to use it, and any prerequisites. Example: 'Retrieve a specific message from iCloud Mail by ID. Call mail_list_mailboxes first to discover available mailboxes, then use a message ID from mail_search_messages to fetch full content including headers and body.'
• Document output schemas for all tools. Specify the structure of returned objects, field types, and which fields are safe to pass to downstream tools. Example: mail_get_message returns { message_id: string, subject: string, from: string, date: string (ISO 8601), mailbox_id: string }
• Add error handling with recovery guidance. Wrap tool implementations to catch exceptions and return structured errors: { error: 'mailbox_not_found', message: 'Mailbox ID xyz not found. Call mail_list_mailboxes to see available mailboxes.', retryable: false }
• For calendar_create_event, add a dry_run parameter (boolean, default false) to preview the event before creation. Return the event object without persisting when dry_run=true, enabling agents to confirm before committing.

Inferred effective spec: 2026-07-28+.

• Relies on Dynamic Client Registration (deprecated) - use Client ID Metadata Documents (CIMD)