Four tools with clear verb-noun naming (list_chains, rpc_call, get_block_number, get_balance). All have descriptions (avg 150 chars, within 10-1024 range). Input schemas use Zod with enum constraints for chain parameter. However, descriptions lack WHEN/WHY guidance for tool selection, and output schemas are not formally documented. Error handling returns structured fail() responses but lacks recovery guidance. No tool annotations (readOnlyHint). Parameters are well-typed but descriptions could be more explicit about constraints and dependencies.

• Add formal output schema documentation to each tool. Use JSDoc or inline comments: '@returns {object} {chain: string, blockNumber: number, raw: unknown}'
• Enhance tool descriptions with WHEN/WHY guidance. E.g., 'Use rpc_call for arbitrary JSON-RPC methods not covered by get_block_number or get_balance. Prefer convenience tools when available.'
• Add readOnlyHint: true to all four tool definitions to signal to clients that these are safe to retry and cache.
• Improve error messages with actionable recovery steps. E.g., catch RPC errors and return: 'RPC error on {chain}: {error.message}. Verify chain slug via list_chains().'
• Document parameter constraints in descriptions. E.g., address parameter: '0x-prefixed EVM address (40 hex chars after 0x prefix)' instead of just '0x-prefixed EVM address.'