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

No annotations are provided, so the description carries the full behavioral burden. It says nothing about invalid-input handling, accepted case, numeric range limits (e.g. 1-3999 for Roman numerals), or which direction applies when both parameters are supplied, which matters for a two-optional-parameter tool.

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?

A single short sentence with the verb and both directions front-loaded, and no filler. It is efficient, though its brevity is part of why the usage and parameter gaps remain unfilled.

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 simple pure converter with no output schema and no annotations, the description is barely adequate: it establishes the conversion but omits direction selection, input validation behavior, and the return shape. Nothing is misleading, but an agent has to guess on the one point that actually matters (which parameter to send).

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 baseline is 3. However, the schema strings are trivial ('Roman to process', 'Number to process'), and the description does not clarify the mutual-exclusivity or precedence of the optional 'roman' and 'number' parameters, so it adds no real meaning beyond 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 a specific verb (Convert) and both resources (Roman and Arabic numerals), so the purpose is unambiguous. It does not, however, distinguish itself from siblings like x402-to-roman or x402-from-roman, which cover the same one-directional conversions.

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 when-to-use guidance, no prerequisites, and no mention of the closely related siblings (x402-to-roman, x402-from-roman, x402-format-roman-num) that an agent could confuse this with. The agent must infer usage entirely from the name.

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