Strong foundation with 27 well-defined tools, comprehensive schemas using Zod validation, and clear descriptions for most tools. All tools have explicit input schemas with type constraints (regex patterns, enums, min/max bounds). Descriptions are generally 50-200 chars and explain WHAT the tool does and WHEN to use it. However, some parameter descriptions lack actionable detail (e.g., 'Candle interval' doesn't specify valid values like '1m', '5m', '1h'), and output schemas are not documented. Error handling is present but generic. Tool naming follows verb_noun convention well (order_create, order_execute, portfolio_snapshot). Composition is excellent, tools chain naturally (order_preview → order_execute, portfolio_snapshot for context). No secrets exposed as parameters. Confirmation gates on destructive operations (order_create, order_modify, order_cancel) are well-designed.

• Document output schemas for all tools. For example, portfolio_snapshot should declare: {holdings: [{symbol, quantity, avgCost, currentPrice}], buyingPower: {KRW, USD}, openOrders: [{orderId, symbol, quantity, price}], warnings: [string]}. Use TypeScript interfaces or JSON Schema in comments.
• Add enum constraints or valid-value lists to parameter descriptions. For candles, specify: 'interval: one of 1m, 5m, 15m, 1h, 1d, 1w, 1M'. For confirmation fields, show the exact required string (e.g., 'confirmation: must be exactly "I understand this may place a real Toss Securities order"').
• Implement error recovery guidance. When a symbol is invalid, return: 'Invalid symbol "XYZ". Try prices() with a valid symbol, or call stock_info() to search available stocks.' Classify errors as retryable (network timeout) vs user-fixable (invalid symbol) vs fatal (auth failure).
• Add per-tool success/failure details for batch operations. If orders_closed returns 100 orders but 5 failed to fetch, return {success: 95, failed: 5, errors: [{orderId, reason}]} instead of a blanket error.
• Migrate from STDIO to HTTP+SSE or Streamable HTTP transport to enable remote deployment and hosted client compatibility. STDIO limits the server to local CLI use only.