Bank of England IADB MCP has well-structured tool definitions with clear naming (verb_noun pattern) and comprehensive descriptions. All 6 tools have explicit schemas with typed properties. However, several parameters lack descriptions (e.g., 'last' in convenience tools has description but lacks min/max bounds), and output schemas are not formally documented. Error handling is present but minimal, no recovery guidance or actionable error messages. The server is domain-focused and read-only, which reduces complexity, but parameter validation rules and output structure documentation would elevate it to 75+.

• Document output schemas for all tools. Add a 'returns' section to each tool definition specifying the JSON structure, field types, and example values. E.g., 'Returns: {series: [{seriesCode: string, observations: [{date: string (ISO 8601), value: number}]}]}'.
• Add min/max constraints to 'last' parameter: 'Number of most-recent observations (default 10, min 1, max 365).' This prevents invalid inputs and guides LLM reasoning.
• Enhance error messages with recovery hints. E.g., 'Invalid series code: BADCODE. Call list_known_series to see available codes, or use get_series with a valid BoE IADB code.'
• Clarify date format preference in get_series description. Recommend ISO 8601 ('YYYY-MM-DD') as primary and note that 'DD/Mon/YYYY' is also accepted for backward compatibility.
• Update series_codes schema to use oneOf: [{type: 'array', items: {type: 'string'}}, {type: 'string', description: 'Comma-separated codes'}] to formally declare both formats.