Lunar Calendar MCP Server

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden. It discloses the comprehensive analysis returned (eight characters, day master element, etc.), which is valuable behavioral context. However, it doesn't mention error handling, rate limits, authentication needs, or computational requirements, leaving gaps for a tool that performs complex calculations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is appropriately sized and front-loaded with the core purpose in the first sentence. Each subsequent sentence adds value by explaining BaZi, listing return components, and stating the tool's essential use. Minor redundancy exists in explaining Chinese metaphysics concepts, but overall structure is efficient.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given no annotations and no output schema, the description partially compensates by detailing return components. However, for a complex fortune-telling tool with 2 parameters, it lacks information on output format, error cases, or example usage. The description is adequate but has clear gaps in operational context.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents both parameters thoroughly. The description adds no parameter-specific information beyond implying birth date/time is used for calculation. Baseline 3 is appropriate since the schema does the heavy lifting, though the description doesn't compensate with additional semantic context.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the specific action ('Calculates BaZi') and resource ('based on birth date and time'), distinguishing it from siblings like 'calculate_bazi_compatibility' which focuses on relationships rather than individual analysis. It provides a concise definition of what BaZi is and what the tool does.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies usage for understanding 'destiny, personality, and life path' but doesn't explicitly state when to use this tool versus alternatives like 'get_daily_fortune' or 'check_zodiac_compatibility'. No guidance is provided on prerequisites or exclusions, leaving usage context somewhat vague.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.