FinAgent MCP server demonstrates solid foundational quality with well-defined tool schemas and consistent descriptions. All 7 tools have explicit JSON Schema definitions with typed parameters and descriptions. Tool naming follows verb_noun patterns (list_accounts, get_holdings, place_crypto_order). However, several critical gaps prevent a higher score: (1) Output schemas are not documented, the server defines inputs but provides no visible response schema definitions for any tool, which prevents LLMs from planning downstream calls. (2) Error handling is undocumented, no guidance on recovery strategies, error classification, or actionable messages. (3) Tool descriptions, while present, are functional but not optimized for LLM reasoning, they average ~100 chars and lack WHEN/WHY context. (4) Parameters like 'includeBalances' and 'groupBy' lack constraint documentation in descriptions. (5) One write operation (place_crypto_order) has dry_run defaulting to true, which is safe, but lacks explicit confirmation/dry-run pattern guidance. The code is well-structured with Zod schemas, TypeScript typing, and proper middleware (validation, error handling, rate limiting), but the MCP interface itself is incomplete for production agent deployment.

• Document response schemas for all 7 tools. Define the structure of list_accounts response (e.g., { accounts: [{id, name, type, balance}], total_count }), list_transactions response (e.g., { transactions: [{id, date, merchant, amount, category}], next_cursor }), and others. This is critical for LLM chaining.
• Add structured error documentation. Define common error cases (invalid date range, account not found, rate limit exceeded) and provide actionable recovery hints in each tool's description, e.g., 'If account not found, call list_accounts() to see valid IDs.'
• Expand tool descriptions to 150 - 250 chars with explicit WHEN/WHY guidance. Example: 'Returns transactions for a user account, filtered by date, merchant, or category. Use this to fetch transaction history; use spending_summary for aggregated spending patterns by category or merchant.'
• Enhance parameter descriptions with natural language constraint hints. For 'window' parameter: 'Time window for summary (7d=last week, 30d=last month, 90d=last quarter, 1y=last year). If you have specific dates, use start/end instead.'
• Update place_crypto_order description to explicitly state: 'Supports dry-run mode (default) for testing. Set dry_run=false to place a live order. Dry-run returns order preview without executing.'
• Add pagination guidance to list_* tools. Document that limit caps results (max 1000 for list_accounts, 500 for list_transactions) and provide next_cursor or offset in response if more results exist. State: 'For large result sets, use limit and offset to paginate.'

Inferred effective spec: <=2025-11-25.

• Relies on Logging (deprecated) - log to stderr or use OpenTelemetry