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. It only states that a conversion happens, but does not disclose the conversion factor (1000 vs 1024), output format, or — critically — how a conversion is performed when the input schema has zero parameters. This is minimally informative but not misleading.

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?

The description is very short and starts with the key action, but it repeats the tool name in the 'Mb To Gb:' prefix. The redundancy wastes a few words, and the brevity comes at the cost of omitting useful context. It is concise, but not a model of well-structured tool documentation.

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 conversion tool with no annotations, no output schema, and an empty input schema, the description leaves too much unexplained. It does not state the output unit, precision, binary/decimal convention, or why no input parameters are declared. An agent could not confidently determine the exact behavior without probing the tool.

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 parameters, and schema description coverage is 100%. Per the rubric, this sets a baseline of 4. The description adds no parameter-level detail because there are no parameters to document, though it also fails to explain how the value to convert is expected to be provided.

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 states a specific verb and resource: 'Convert mb to gb.' This clearly indicates a megabyte-to-gigabyte conversion and differentiates it from the sibling tool gb-to-mb by direction. However, it does not clarify whether 'mb'/'gb' mean megabits/gigabits or megabytes/gigabytes, and it leaves decimal vs. binary conversion 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?

No usage guidance is provided. The description does not say when to prefer this tool over alternatives like x402-gb-to-mb, x402-units-convert, or x402-data-size, nor does it mention any exclusions or prerequisites. The intended use is only implied by the name and description.

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