Three tools with complete Zod schemas and basic descriptions in Japanese. All tools have input schemas with typed parameters and descriptions. However, descriptions are minimal (10-30 chars in English translation), lack actionable context for LLM selection, and do not explain when to use each tool vs. alternatives. No output schemas documented. Error handling exists but returns generic Japanese error messages without recovery guidance. Tool names follow verb_noun pattern (list-, search-, analyze-) but descriptions do not explain dependencies or prerequisites. No tool annotations (readOnlyHint, etc.). Composition is reasonable, three distinct concerns, but descriptions fail to guide LLM reasoning.

• Expand tool descriptions to 100-200 chars. Example: 'list-s3-log-files: Retrieve S3 access log file paths within a date range (UNIX timestamps in seconds). Returns array of S3 object keys. Use this first to discover available logs before calling search-s3-logs or analyze-s3-logs.'
• Document output schemas in tool definitions. E.g., 'Returns: { files: string[] }' for list-s3-log-files; 'Returns: { matches: Array<{line: string, ip: string, status: string, ...}>, count: number }' for search-s3-logs.
• Add tool annotations: readOnlyHint=true for all three tools to signal to LLMs that these are safe to call without confirmation.
• Enhance error messages with recovery guidance. Instead of 'エラー: バケット not found', return 'Bucket not found. Verify S3_BUCKET environment variable is set and the bucket exists in your AWS account.'
• Add parameter constraints to descriptions. E.g., 'start: UNIX timestamp in seconds (e.g., 1704067200 for 2024-01-01). Must be <= end. Logs older than 90 days may be archived.'