Single tool with basic schema and minimal descriptions. Tool name 'get-current-time' follows verb_noun convention (+). Input schema uses Zod enum for format parameter with optional flag (+). Tool description (19 chars: '現在時刻を取得するツール') is also critically short, providing no context on WHEN to use it or WHAT it returns. No output schema documented. No error recovery guidance beyond generic McpError. No parameter constraints on format values documented in description text (LLMs cannot read Zod schema). Overall: functional but severely under-documented for LLM reasoning.

• Expand tool description to 50 - 150 chars: 'Returns the current Japan Standard Time (JST) in the requested format. Use this to provide time-aware context in responses. Supports full datetime, date-only, or time-only formats.'
• Expand parameter description: 'Format for the timestamp output. "full" returns date and time (e.g., 2025-01-15 14:30:45), "date" returns date only (2025-01-15), "time" returns time only (14:30:45). Defaults to "full".'
• Document output schema in code comments: 'Returns {content: [{type: "text", text: string}]} where text is the formatted JST timestamp.'
• Improve error message: throw new McpError(ErrorCode.InvalidRequest, `Invalid format: got "${format}". Must be one of: full, date, time.`) to enable LLM self-correction.
• Migrate from STDIO to HTTP+SSE or Streamable HTTP transport to enable remote access and hosted client compatibility.