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

No annotations are provided, so the description carries the full burden. It does usefully disclose the discrete return set (1, 0, -1), but says nothing about how the string-typed 'value' and 'period' inputs are interpreted, whether output is deterministic, or what happens on malformed input.

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?

One well front-loaded sentence that puts the operation and return values first. The pricing/emoji tack-on is noise but does not bury the core 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?

For a simple sampling function this is close to adequate, and the description supplies the return values in lieu of an output schema. However, with both inputs typed as untyped strings and no clarification of numeric format, an agent cannot be fully confident how to call it.

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 0% for both parameters, and the description only repeats the parameter names ('at a value and period') without adding type, format, units, or range meaning. For a 2-parameter tool with no schema documentation, this leaves genuine ambiguity.

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?

States a specific verb and resource ('Samples a square wave at a value and period') and even discloses the output set ('1, 0, or -1'), which lets an agent distinguish it from siblings like x402-sawtooth-wave, x402-triangle-wave and x402-step-function. It never names an alternative explicitly, but the waveform identity is unambiguous.

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 statement of when to use this tool versus the other waveform siblings, no prerequisites, and no note on input format expectations. The only extra content is a free-trial/pricing promo, which is commercial not usage guidance.

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