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

No annotations exist, so the description must carry the full burden of behavioral disclosure — and it discloses nothing at all. It does not state whether the call is read-only, what inputs factor into the 'percentage of' computation, what it returns, or any edge-case or scoping constraints.

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?

At seven words, the description is brief, but this is under-specification, not conciseness — no information is front-loaded because none exists. Every word is wasted on repeating the tool's own name with no explanatory content.

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 output schema, no annotations, empty parameters, and a tautological description, an agent has nothing to predict the call's behavior, inputs, or return value. Given a sibling list of roughly a thousand tools with many percentage variants, the definition is completely inadequate for selection or invocation.

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 input schema is empty (0 parameters, 0 required), so there are no parameters the description could clarify or misrepresent. Per the 0-param baseline, the schema fully covers this dimension; the description earns no credit but also creates no parameter confusion. A higher score would overstate the value of a definition that adds nothing elsewhere.

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 literal tautology: 'Percentage Of: Percentage Of' merely restates the tool name with no verb, resource, or behavior. In a catalog with over a thousand siblings including near-identical names like x402-percent-of, x402-percent-of-value, x402-proportion-of, and x402-ratio-of, it gives an agent zero ability to understand what the tool computes.

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 versus the closely related x402-percent-of, x402-percent-of-value, x402-percentage-change, or x402-proportion-of. The description offers no context, exclusions, or alternatives, so an agent cannot distinguish picking this tool from any of its dozen percentage siblings.

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