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

With no annotations, the description carries the full burden, but it only restates the conversion with no additional behavioral context. It does not disclose unit ambiguity (e.g., metric vs. short ton), rounding/precision behavior, output format, or how the input value is supplied given the empty parameter schema.

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 extremely short and front-loaded, containing only a label and one sentence. It is concise, though the 'Tons To Kg' prefix is redundant with the sentence 'Convert tons to kg,' wasting a few words.

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?

The tool is simple, but the description does not mention input format, unit system, return format, or how to invoke it despite having no parameters and no output schema. An agent would know the general intent but not the operational details needed to call it correctly.

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?

There are zero parameters and schema coverage is trivially 100%, so the description does not need to document individual parameters. However, it also fails to clarify how the numeric value to convert is provided, which is notable given the empty schema. The baseline of 4 applies because no parameter documentation burden exists.

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 action ('Convert tons to kg') with a clear resource and conversion direction. It is unambiguous, though it essentially repeats the tool name and does not explicitly distinguish itself from sibling conversion tools like x402-kg-to-tons.

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 is given about when to use this tool versus alternatives such as x402-kg-to-tons or x402-pounds-to-kg. The context implies a conversion use case, but no conditions, exclusions, or alternative recommendations are provided.

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