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: not whether it computes, simplifies, or converts, not the output shape, and not how 'ratio' and 'width' interact.

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 it is under-specified rather than concise — the single sentence duplicates the tool name and earns no place. There is no front-loaded action statement because there is no content at all.

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?

With no annotations, no output schema, and an ambiguous two-parameter contract, the description should be doing substantial work; instead it is completely inadequate, leaving an agent unable to determine what input format is expected or what the tool returns.

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 two parameters are technically documented, giving a baseline of 3. However, the schema text itself ('Ratio to process', 'Width to process') is near-meaningless, and the description does nothing to clarify how a ratio string and a width combine.

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 a tautology that simply restates the tool name twice ('Aspect Ratio Calc: Aspect Ratio Calc') without stating what the tool actually computes or returns. The name hints at a domain, but the description adds no verb or resource specificity beyond it.

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 whatsoever on when to use this tool, when not to, or which sibling (e.g. x402-aspect-ratio, x402-ratio-simplify) it differs from, despite an enormous sibling list.

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