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

With no annotations, the description carries the full behavioral burden. It mentions the default value of t (0.5), which is genuinely useful since 0 required parameters makes the default significant, but it does not state what happens for out-of-range t values, whether input is clamped, or what the output format is (no output schema).

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 a single tight sentence that front-loads the formula and then the parameter expectations. It is efficient and appropriately sized for a simple math utility, with no wasted words.

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?

Given the complexity (a basic interpolate function with three parameters and a default), the description is largely complete for the core operation. However, with no output schema and no annotations, it should ideally specify clamping behavior, input type expectations, and the return form to be fully self-contained.

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 100% and the schema provides descriptions for a, b, and t (though generic, e.g. 'A to process'). The description adds meaning by defining t as a factor 0-1 with a default of 0.5, which is arguably more informative than the schema's generic descriptions, but it still does not fully compensate for the poor quality of the schema parameter descriptions.

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 states a specific verb (Linearly interpolate) with the resource and formula semantics (between two values a and b by a factor t). It does not explicitly distinguish itself from sibling tools like x402-inverse-lerp, x402-interpolate, x402-lerp-value, or x402-remap, but the described behavior is clear enough for an agent to understand what it does.

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?

No when-to-use guidance is provided, and no alternatives are named. The description does not mention when this tool should be selected over x402-inverse-lerp, x402-interpolate, or x402-remap, all of which are closely related siblings in the tool list.

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