6 tools with basic-to-moderate quality. All tools have descriptions (meeting minimum bar), and input schemas are present with types and parameter descriptions. However, descriptions are generic and brief (averaging ~100 chars), lacking the LLM-optimized depth (50-200 chars baseline) that helps agents select and invoke correctly. Output schemas are entirely undocumented, the source shows tool registration but no explicit return type specifications, forcing LLMs to infer results. Parameter constraints are minimal: 'chain' accepts free-form strings with only a default of 'ethereum', not enums; block numbers and pagination parameters lack min/max bounds. Error handling is invisible in the provided code, no recovery guidance, no categorization of retryable vs fatal errors. Security: API keys (ETHERSCAN_API_KEY, BSCSCAN_API_KEY) are loaded from environment (good), but there's no evidence of input validation, rate limiting enforcement, or audit logging in the snippet. Tool composition is reasonable, each tool has a single responsibility, but downstream tool chaining is not evident. The 'analyze_whale' tool is the most sophisticated, promising 'comprehensive' analysis, but its return structure is not documented.

• Document output schemas for all 6 tools. Define return type (object, array, etc.), required fields, field types, and descriptions. Example for check_balance: {"balance": {"type": "string", "description": "Balance in wei"}, "address": {"type": "string"}, "chain": {"type": "string"}}
• Convert 'chain' parameter to enum: {"type": "string", "enum": ["ethereum", "bsc"], "description": "Blockchain network"}. Apply to all 6 tools.
• Add numeric bounds. For get_transactions: start_block (min 0), end_block (min start_block, max current_block), page (min 1), offset (min 1, max 100). Document in parameter description.
• Example: check_balance → 'Get the native cryptocurrency balance (ETH or BNB) for a wallet address. Returns balance in wei. Use this to check account funding or verify transfers.'
• Document error responses with recovery guidance. Example: If address is invalid, return {"error": "Invalid address format. Expected 42-character hex string starting with '0x'. Example: 0x1234567890123456789012345678901234567890"}
• Add address validation: require format like /^0x[a-fA-F0-9]{40}$/ for Ethereum (42 chars with 0x prefix). Document constraint in parameter description.
• Document pagination limits. If tools cap results at 100 per page, state: 'Maximum offset: 100. Use page parameter to fetch additional results.'
• Add return field documentation for analyze_whale: Define whale_class (enum: small_holder, mid_whale, mega_whale, etc.), activity_patterns (object with metrics), and risk_metrics (object with scores). Specify whether each is required.