18 tools with complete JSON Schema definitions, strong naming conventions (verb_noun prefix), and reasonable descriptions. Most tools have type-constrained parameters with enums (currency, orderType, side, interval). However, descriptions are terse (many under 100 chars, some under 50), missing context on when to use tools and dependencies. Parameter descriptions are minimal or absent for some tools. Output schemas not documented. Error handling present but not guide-based. Security-sensitive tools (create/modify/cancel order) have guardrails in code but not described in tool metadata.

• Document output schemas for all tools in the description or as separate metadata. Example: 'Returns { accounts: Array<{ accountSeq: number, accountName: string, ... }>, totalCount: number }'.
• Expand read-only tool descriptions to 80-150 chars. Add context: 'Get real-time bid/ask orderbook for a stock symbol, use before placing limit orders to choose a competitive price.' vs 'Get orderbook data for one KRX or US stock symbol.'
• Create a dedicated tool or capability to query active guardrails (e.g., 'get_active_guardrails') that returns symbol allowlist, daily limit, sell/market restrictions, account locks. Agents can call this first to understand constraints.
• Move confirmation/lock requirements into the tool description summary, not just parameter docs. Example: 'Create a securities order. Requires confirmOrderAction=true if TOSSINVEST_REQUIRE_ORDER_CONFIRMATION is enabled.'
• Refactor order-mutating tool error messages to be agent-friendly: 'Sell orders are disabled by this MCP server configuration. Contact the system administrator to enable sell orders.' Let the user handle the configuration gap, not the LLM.
• Add optional parameter 'use_environment_account' (default false) with description 'If true, ignore accountSeq and use TOSSINVEST_ACCOUNT from environment. Fail if env is not set.' This makes implicit coupling explicit.
• Document pagination: read-only tools returning lists (get_holdings, get_prices with multiple symbols) should clarify if results are capped and offer parameters for pagination.