Server has 12 tools with complete input schemas and descriptions in Japanese. However, descriptions are minimal (10-30 chars), lack actionable context for LLM selection, and omit critical details like prerequisites, return types, and error guidance. No output schemas documented. Parameter descriptions are present but generic. No error handling patterns visible. Tool naming follows verb_noun convention (connect_, disconnect_, get_, list_, execute_) but lacks clarity on risk/side effects in descriptions. Security concern: passwords exposed as parameters (connect_database, add_profile) violates secret-injection pattern.

• Move password/credentials to server-side environment variables or vault. Use profileName-based authentication only in tool parameters. Update connect_database and add_profile to accept only host, port, user, database, profileName, no password param.
• Expand all tool descriptions to 50-200 characters. Include: what the tool does, when to use it vs similar tools, and what it returns. Example: 'connect_database: Establishes a MySQL connection using host/port/user. Returns connection status and available databases. Use before executing queries. Saves connection as a named profile for reuse.'
• Document output schemas for all tools. Define return types as JSON Schema objects. Example for get_databases: {type: 'object', properties: {databases: {type: 'array', items: {type: 'string'}}, total: {type: 'number'}}}.
• Add error handling with recovery guidance. Catch connection errors, query syntax errors, and timeouts. Return structured errors: {error: 'Connection failed', reason: 'Host unreachable', suggestion: 'Verify host and port, then retry.'}.
• Validate execute_query input: enforce parameterized queries, reject raw SQL with suspicious keywords (DROP, TRUNCATE), and limit result set size. Return clear validation errors: 'Query rejected: DROP not allowed. Use parameterized queries with ? placeholders.'