Server demonstrates solid fundamentals: all 6 tools have clear descriptions (avg 150 chars), proper verb-noun naming, and complete zod-based input schemas with parameter descriptions. Tool composition is clean, each tool has one responsibility. However, output schemas are not documented in code or README, parameter constraints lack formal enums (e.g., 'operator' accepts free-form strings instead of enum), and error handling, while present, does not consistently guide recovery. No tool annotations (readOnlyHint/destructiveHint) despite clear risk profiles. Baseline: 194 chars avg description (this server ~150), 100% of A+ tools have param descriptions (this server: 100%), but output schema documentation is missing.

• Add output schema documentation to README or inline JSDoc. Example: 'Returns: {content: [{type: "text", text: string}]}'
• Convert 'operator' parameter to zod enum: z.enum(['add', 'subtract', 'multiply', 'divide']).describe(...)
• Convert 'units' parameter to zod enum: z.enum(['celsius', 'fahrenheit']).describe(...)
• Add tool annotations via server.tool() options: {readOnlyHint: true} for read tools, {destructiveHint: true} for create_note
• Enhance error messages in list_files to suggest valid paths when directory not found: 'Path not found. Try: ./src, ./dist, or use pwd to verify current directory.'