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 discloses no behavioral traits: no return-value shape, no input handling, no side effects, no format expectations. With an empty input schema and an empty description, an agent receives zero behavioral information.

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 extremely short but under-specified. 'Weighted Mean: Mean of weighted.' is a tautology that repeats the tool name. There is no structure, no formula, no example, and no notes about what values are averaged. This is not conciseness; it is missing 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 statistical tool surrounded by many similar siblings, this description is entirely inadequate. There is no output schema, no annotations, no parameters to infer behavior from, and no usage example. The sibling list includes x402-weighted-average and x402-weight, making the lack of disambiguating context especially damaging.

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?

The schema has 0 parameters, so there is no parameter documentation needed, giving a baseline of 4. However, the tool named 'weighted-mean' claims to compute a weighted mean with 0 parameters, which is semantically impossible for a real statistical operation. The description does not clarify this contradiction.

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 is 'Weighted Mean: Mean of weighted.' which merely restates the tool name. It lacks a specific verb and resource, telling an agent nothing about what the tool actually does. It does not distinguish it from siblings like x402-weighted-average or x402-weighted-median.

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 guidance on when to use this tool versus alternatives such as x402-weighted-average, x402-mean-of, or x402-median. Context signals show 0 parameters and no annotations, and the description gives no scenario, prerequisites, or exclusions.

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