Cyclic Index

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

Annotations already declare readOnlyHint true, destructiveHint false, idempotentHint true, so the description does not need to repeat those. It adds meaningful context that the index is based on outer planet separations and used for crisis periods. However, it does not detail behavior for invalid inputs, edge cases, or output format.

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 brief: three lines including the purpose and an example. The group and cost metadata could be better placed but do not detract. Front-loading is effective. Every sentence adds value.

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 specialized index calculation, the description lacks details on what the output contains (no output schema), how to interpret the results, and any limitations. The example only shows input. The annotations already cover safety, but the description could be more complete.

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 0%, so the description must compensate. It explains startYear and endYear through an example, but does not define them explicitly, and the optional 'pairs' parameter is completely unexplained. This leaves ambiguity for the agent.

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 tool calculates the André Barbault Cyclic Index for a date range to indicate global crisis periods. The verb 'calculate' and specific resource 'Cyclic Index' make the purpose unambiguous. The sibling tools are numerous but none perform this exact calculation, so it is well-distinguished.

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 the tool is used when a global crisis indicator over a date range is needed, but it does not explicitly state when to use this tool versus alternatives like planetary_cycles or other index tools. No when-not or alternative guidance is provided.

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