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

No annotations exist and the description discloses no behavior: no formula, no side effects, no return value, and no handling of missing parameters despite none being required. The text only repeats the tool name and adds no behavioral context.

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 text is short but is under-specification rather than concision. The single sentence 'Discount Calc: Discount Calc' contains zero useful information and does not earn its place in the definition.

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?

For a calculation tool with no annotations, no output schema, and three string parameters, the description omits the calculation formula, parameter semantics, optionality behavior, and return format. An agent cannot reliably invoke or interpret this tool correctly.

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 descriptions cover all three parameters 100%, so the baseline is 3, but the parameter descriptions ('Price to process', 'Percent to process', 'Discount to process') merely restate the parameter names. The description adds no formula, units, or relationship between price, percent, and discount.

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?

Description is 'Discount Calc: Discount Calc', a tautology that restates the tool name with no verb, no resource, and no stated result. It cannot distinguish this tool from the similarly named sibling x402-discount or the many percent-related tools.

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 guidance is provided about when to use this tool, what scenarios it fits, or which sibling should be used instead. The large sibling list includes x402-discount and numerous percent calculators, but the description gives no routing help.

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