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 not state whether inputs are numeric, what unit system is used, whether negative/zero dimensions are handled, or the return shape. For a pure calculation tool this is a notable gap in behavioral context.

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?

Very short and front-loaded. It is concise, though arguably too terse to be maximally useful—the terseness is a transparency issue rather than a structure flaw.

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 three-parameter math tool with no annotations, no output schema, and a highly similar sibling nearby. The description fails to clarify the calculation formula, units, or the distinction from x402-prism-volume, leaving the agent under-equipped.

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 three parameters (width, height, length) are already documented in the schema. The description adds nothing beyond the name regarding parameter meaning or type beyond the obvious geometric interpretation. Baseline 3 applies.

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 computation (volume of a rectangular prism) via name and a terse restatement. However, it does not differentiate from the very similar sibling x402-prism-volume, leaving ambiguity about which tool to select for a rectangular vs general prism.

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 guidance on when to use this versus alternatives like x402-prism-volume, x402-box-volume, or x402-cuboid-diagonal. The agent must infer the distinction from the name alone.

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