Single tool 'create-image' has a well-structured schema with comprehensive parameters, clear enum constraints, and detailed descriptions. However, the tool description, while present, is somewhat generic and could better explain when to use it vs alternatives or error recovery paths. Parameter descriptions are generally good but some lack actionable detail (e.g., 'User identifier for tracking' doesn't explain what this is used for). Output documentation is absent, the tool returns base64 or file paths but no schema is documented for what the response structure contains. Error handling is basic (throws Error with messages) but lacks recovery guidance or categorization. Composition is good: one focused tool doing one thing. Overall definition quality is above average but falls short of production-grade due to missing output schema documentation and incomplete error recovery guidance.

• Document the output schema explicitly. For base64 output, return {data: string, format: string, metadata?: {...}}. For file_output, return {file_path: string, format: string, size_bytes: number}. This allows LLMs to plan what to do with the result.
• Enhance error messages with recovery guidance. Instead of 'Invalid size "1024x999"', return 'Invalid size "1024x999". Supported sizes: 1024x1024, 1536x1024, 1024x1536, or auto. For aspect ratios, use: square (1:1), landscape (16:9), portrait (9:16).'
• Clarify the 'user' parameter: 'OpenAI user ID for tracking usage. If not provided, requests will not be attributed to a specific user for analytics.'
• Update tool description to mention: 'This tool calls OpenAI's image generation API and will incur charges based on the number and size of images generated. n parameter determines count (1-10). Use sparingly in production.'
• Merge aspect ratio examples into the size enum by providing a mapping endpoint, or document that aspect ratios must be translated to exact dimensions before passing to the tool. Currently the description misleads by listing unsupported enum values.
• In 'output_format' parameter description, add: 'Note: If background=transparent, output_format must be png or webp, not jpeg.'
• Add to tool description or a separate 'rate_limits' field: 'OpenAI enforces rate limits (typically 5 req/min for free tier, higher for paid). Batch multiple image requests within a single call using the n parameter to stay under limits.'
• Consider adding a 'dry_run' or 'preview' parameter that returns estimated cost without generating images, following the confirmation-request pattern for cost-intensive operations.