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

No annotations are present, so the description bears the full burden of explaining behavior, but it says nothing about side effects, output format, error cases, or computational behavior. The text merely repeats the tool's name and provides zero behavioral information.

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 but not concise in a useful way; it is repetitive, ungrammatical, and under-specified. 'Ratio of of' is not efficient communication, it is a malformed fragment that wastes the little space it occupies.

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, no parameters, and a near-meaningless description, the tool lacks all context an agent needs to call it correctly. There is no statement of input, output, computation, or relationship to similar tools, making it effectively unusable from its definition.

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?

The tool has zero parameters, so the rubric baseline is 4, but the description adds no meaningful clarification about how the ratio is specified or computed. Because there are no parameters to document, the schema imposes no burden, yet the description still fails to confirm that the tool takes no arguments or explain how the ratio is passed in.

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 'Ratio Of: Ratio of of.' is a tautological restatement of the tool name and contains a grammatical error ('of of'). It does not state what resource is acted on, what input is expected, or what kind of ratio result is produced, so an agent cannot tell what this tool does or why it exists.

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 about when to use this tool, what kinds of inputs it expects, or how it differs from the many related siblings such as x402-ratio-simplify, x402-ratio-to-percent, x402-percentage-of, and x402-proportion-of. The description provides no basis for selecting it over alternatives.

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