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

No annotations are provided, so the description carries the full burden - and it discloses nothing. It does not say whether this is a pure computation, what happens with missing inputs (0 required params), or what the result represents.

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 short, but that brevity reflects under-specification rather than conciseness. The single sentence is a circular restatement and is front-loaded with no useful information.

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?

A 3-parameter computation tool with no annotations and no output schema needs the description to explain inputs and semantics. Nothing is explained, so the definition is inadequate for correct 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?

Schema description coverage is 100%, so the baseline is 3 even though the description adds nothing about value/years/inflation. The schema descriptions ("Value to process") are themselves thin, but the structured fields technically cover all three parameters.

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?

"Purchasing Power: Power of purchasing." is a tautology that restates the tool name without stating any verb, resource, or computation. An agent cannot tell what the tool actually computes (an inflation-adjusted value? a currency purchasing-power index?) from this text.

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, no alternatives named, no exclusions. Sibling tools like x402-inflation-adj and x402-real-rate plausibly overlap, yet no differentiation is offered.

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