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

With no annotations provided, the description carries the full burden of behavioral disclosure, and it discloses nothing. It does not state how weights and values are supplied, what computation is performed (e.g., sum of weighted values divided by sum of weights), or any edge-case behavior, so the agent has no idea what invoking this tool will do.

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?

At six words the description is short, but this is under-specification masquerading as conciseness. The phrase "Average of weighted" merely rephrases the tool name and earns no place, and nothing of substance is front-loaded because nothing of substance is present.

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?

Even with low structural complexity (0 params, no nested objects), the description is completely inadequate. There is no output schema, so the description must explain return values and invocation, yet it explains neither, and the presence of near-synonymous siblings makes this lack of 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 input schema has zero properties, so there are no parameters whose semantics the description could elaborate on; the 0-parameter baseline of 4 applies. The fact that the empty schema is unexplained is a contextual gap rather than a parameter-semantics gap.

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 "Weighted Average: Average of weighted" is essentially a restatement of the tool name and adds no real semantic content. It does not identify a distinct verb, resource, or input/output relationship, and it fails to differentiate from close siblings like x402-weighted-mean and 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?

The description provides no guidance on when to use this tool versus alternatives. There are no usage conditions, exclusions, or mentions of overlapping siblings such as x402-weighted-mean or x402-weighted-median, leaving an agent with no basis for choosing among them.

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