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

No annotations are provided, so the description carries the full burden, and it discloses almost nothing: not the formula applied, not the units expected or returned, not whether inputs are numeric strings or expressions, and not what the response contains. For a calculation tool with zero annotation coverage this is a significant gap.

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?

It is a single short line with zero filler and is front-loaded, which is appropriate for a simple calculator. It is minimal rather than verbose, though the terseness borders on under-specification.

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 two-parameter math tool with no annotations and no output schema, the agent still lacks the computation formula, expected units, string-format expectations, and return shape. The description does not fill these gaps, so it is not complete enough to guarantee a correct call.

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 nominally 100%, so the baseline is 3, but the field descriptions ('Height to process', 'BaseArea to process') are generic placeholders that convey no real semantics. The description does not compensate with the formula (V = baseArea × height) or unit expectations, so it adds no meaning over the schema.

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 names the resource and the operation ('Volume of prism'), so the agent knows this computes a prism's volume. However, it is essentially a restatement of the tool name and does not differentiate from close siblings such as x402-rect-prism-volume, x402-cube-volume, x402-frustum-volume, or x402-pyramid-volume, leaving the prism variant ambiguous.

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 many other volume siblings, no prerequisites, and no note about units or which prism type is assumed. The agent must infer everything from the name.

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