DuoFund MCP has 14 well-named tools with consistent verb_noun patterns (get_, list_, create_, delete_). All tools have descriptions (avg ~80 chars, within baseline 34-392). Input schemas are present and use Zod with enums for constrained fields (scope, type, priority). However, output schemas are NOT documented, responses are formatted as plain JSON text without field-level documentation. Parameter descriptions are minimal (10-30 chars) and lack actionable constraints (e.g., no min/max for numeric fields, no format hints for dates). Error handling is absent, API errors are passed through without recovery guidance. No tool annotations (readOnlyHint, destructiveHint) despite clear risk levels. Composition is sound: tools are single-responsibility and chainable via IDs.

• Add tool annotations to schema: destructiveHint=true for delete_* tools, readOnlyHint=true for list_* and get_* tools. This enables LLMs to reason about side effects.
• Document output schemas for all tools. E.g., get_summary returns {income: number, expenses: number, balance: number, budget_used_percent: number}. Include field descriptions.
• Enhance parameter descriptions with constraints: 'limit (0-1000, default 0 = no limit)', 'date (YYYY-MM-DD format, default today)', 'priority (high=urgent, medium=normal, low=backlog)'.
• Implement error recovery guidance. Catch API errors and return structured responses: {error: 'Category not found', code: 'NOT_FOUND', suggestion: 'Call list_categories() to see available options.'}.
• Add pagination to list_* tools: accept limit (1-100, default 20) and offset/cursor parameters. Return {items: [...], total: N, next_cursor: '...'} to support large datasets.