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

The description adds useful behavioral detail beyond the annotations: every response includes the Julian Day Number, elapsed day count, and Calendar Round, and the correlation constant is parameterized rather than hidden. The destructiveHint annotation is not directly contradicted because the description never explicitly promises a side-effect-free operation, though the description reads as a pure converter and would benefit from clarifying what that flag refers to.

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 economical: the first sentence establishes the core bidirectional behavior, the second gives response contents and the correlation design, and the third names target use cases. No filler or redundant restatement of the title.

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?

For a tool with five parameters, no output schema, and two enums, the description is nearly complete: it covers the conversion directions, key response contents, and intended audiences. The residual gap is the unaddressed destructiveHint annotation and the lack of any error-condition guidance, which the schema only partially covers.

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 coverage is 100%, so the parameter burden is already carried by the schema. The tool description adds conceptual value by explaining the role of the correlation constant and the output fields, which helps an agent reason about correctness without needing to re-derive semantics from the schema alone.

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 states a specific operation — bidirectional conversion between Gregorian dates and Maya Long Counts — and names the exact resource. It clearly distinguishes itself from the sibling astrology/divination tools by emphasizing pure date conversion rather than daily readings or charts.

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 gives clear intended contexts: epigraphy tools, museum and education apps, and civil-date placement. It also explains both invocation directions, but it does not explicitly name sibling alternatives or state when not to use this tool, so it stops short of a 5.

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