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

No annotations exist, so the description carries the full burden and largely fails: it does not state the formula used, units, expected input format, error behavior, or return shape. The one piece of real behavior it conveys is the pricing/auth model (5 free calls per signed wallet), which is genuinely useful context but far from sufficient.

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 very short and front-loaded, so nothing is buried. However, the second sentence is promotional boilerplate rather than specification, so the brevity comes from under-specification rather than disciplined editing.

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 undocumented parameters, the description is the only source of truth and it never says what the tool computes or returns. For a computation tool with two free-form string inputs this 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 0% for two parameters, and the description never mentions inputWork or outputWork at all. It gives no meaning, format, or unit guidance for either argument, so an agent must guess that efficiency = outputWork / inputWork.

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?

"Efficiency: Efficiency calculation" restates the tool name without defining what is being computed (e.g. output/input ratio, energy efficiency, or cost efficiency). No sibling is named or ruled out, and given a catalog of hundreds of math/physics tools, an agent cannot distinguish this from x402-power, x402-work, or x402-energy from the text alone.

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 when-to-use or when-not-to-use guidance, and no mention of the conditions the inputs must satisfy. The only directive content is a pricing note about free trial calls, which does not help select the tool.

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