Tzolkin Day Sign

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the description does not need to confirm read-only behavior. The description adds the specific output fields (number, name, element, direction, keyword), which provides some transparency beyond annotations. No contradictions.

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 short with three sentences, front-loading key output information. It includes a practical example. There is no wasted text, though it could be slightly more structured with a list. Efficient overall.

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 output schema, the description lists return fields, which is helpful. However, it lacks usage guidelines and does not explain the optional location parameters. For a simple tool, it is moderately complete but could better aid agent decision-making among siblings.

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?

Input schema has 100% description coverage for all parameters. The description only mentions an example date and does not add any additional semantics for latitude, longitude, or timezoneOffset. Baseline 3 is appropriate as the schema already documents parameters adequately.

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 it returns a 260-day sacred calendar with specific fields (number, day-name, element, direction, keyword). This differentiates it from many other Mayan calendar tools in the sibling list, but it does not explicitly distinguish from similar tools like mayan_calendar_round or mayan_dreamspell.

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 provides no guidance on when to use this tool versus alternatives. It does not mention any prerequisites, context for when it is appropriate, or when not to use it. The example only demonstrates a request body.

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