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

No annotations are provided, so the description must fully disclose behavior. It isteals nothing: no return type, no handling of edge cases, no input format expectations, no side effects. The descriptionry is merely a label with no behavioral content.

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?

Four works, but this is under-specification rather than effective conciseness. It conveys no actionable content (the description does not even state the operation verb), and there is no structure that surfaces 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?

For a math utility with ambiguous parameters and no output schema, this description is critically incomplete. An agent cannot tell whether to pass an array, a comma-separated string, or separate components, nor what norm or result format to expect.

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?

Although schema coverage is 100%, the parameter descriptions ('A to process', 'V to process', 'Vector to process') are vacuous and do not clarify meaning. The tool description adds no parameter explanation. Thereis are three parameters with unclear relation (a, v, vector) and no indication of how a vector should be represented.

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 'Vector Norm: Vector Norm' is a pure tautology that merely restates the tool name. It does not say the tool computes the magnitude of a vector, nor which norm type (Euclidean, Manhattan, etc.) is returned. An agent gains zero new information 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?

There is no guidance whatsoever about when to use this tool rather than sibling tools such as x402-vector-dot, x402-vector-cross, or x402-normalize-vector. The description provides no context, preconditions, or exclusions.

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