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

No annotations are provided, so the description carries the full behavioral burden, and it discloses nothing: no output units (degrees vs radians), no constraints on n/sides, no note on whether it is a pure computation or an error/throwing operation.

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?

It is short, but the brevity comes from under-specification, not from efficiency; the same phrase is duplicated with a colon, adding zero information. Comparable to a one-word tautology rather than a front-loaded instruction.

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 two undocumented-in-meaning parameters, no annotations, and no output schema, the description supplies none of the missing context (what is computed, in what units, what n vs sides mean). It is completely inadequate.

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% (both n and sides have descriptions), so the baseline is 3 per rubric. However the description adds nothing, and the schema text ('N to process', 'Sides to process') is itself vacuous, leaving the apparent redundancy between n and sides unresolved anywhere.

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 is 'Regular Polygon Exterior: Regular Polygon Exterior', a verbatim restatement of the tool name. It names no verb (compute/calculate) and no output (exterior angle, sum of exterior angles), so it is pure tautology rather than a statement of purpose.

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?

There is no guidance on when to use this tool, when not to, or how it relates to siblings like x402-regular-polygon-interior, x402-regular-polygon-area, or x402-polygon-area. Nothing is stated or even implied.

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