Two tools with solid schema definitions and reasonable descriptions, but missing critical elements for production use. Both tools have explicit input schemas with proper JSON Schema structure and type declarations. Tool descriptions are present and informative (119-132 chars, within the 10-1024 baseline range). However, neither tool has documented output schemas, the descriptions state what data is retrieved but don't specify the structure of the response fields returned by the handler. No error handling guidance (e.g., 'If symbol not found, try a different ticker'). Parameters generally well-constrained with enums where appropriate, but descriptions could be more prescriptive about formats and valid ranges. Missing tool annotations (readOnlyHint, etc.) despite both being read-only operations. No recovery guidance in error cases.

• Add output schema documentation to both tools. Example for stock_price: 'Returns {time_series: {[timestamp]: {open, high, low, close, volume}}, metadata: {symbol, interval, last_updated}}'. This lets agents know what fields to extract and plan downstream logic.
• Replace bare error messages with recovery guidance. Example: 'catch (error) { if (response.status === 404) return {content: [{type: "text", text: `Symbol not found: ${symbol}. Try search_symbols() to find valid tickers.`, isError: true}]} }'
• Add readOnlyHint annotation to both tool schemas: '"_meta": {"readOnlyHint": true}' in inputSchema. Enables clients to mark these as safe operations.
• Enhance parameter descriptions with constraints and hints. For 'symbol', append: '(uppercase letters and numbers, typically 1-5 characters; e.g., AAPL, BRK.B)'. For 'interval', note: 'intraday intervals (1min, 5min, etc.) require premium API access; daily is available on free tier.'
• Document rate limits and quotas in tool descriptions. Example: 'Note: Alpha Vantage free tier allows 5 requests/min. Premium tier supports faster intraday updates.' This sets agent expectations.
• Rename 'stock_price' to 'get_stock_timeseries' or 'fetch_stock_historical_data' for clarity. The tool retrieves a series, not a single price.
• For company_fundamentals, clarify that 'metrics' array batches multiple endpoints. Add: 'Requesting multiple metrics ["income", "balance"] in one call fetches both in a single tool invocation, reducing round-trips.'
• Add error categorization. Distinguish between retryable errors (rate limit, timeout) and user-fixable errors (invalid symbol, missing API key). Return structure like: {isError: true, retryable: true, guidance: '...'} to guide agent retry logic.