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

No annotations are provided, so the description carries the full burden. 'Number discarded' is cryptic and does not disclose what happens to any input, whether anything is mutated or returned, or what the nine parameters actually do.

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 short, but this is under-specification rather than conciseness. A single cryptic clause fails to earn its place because it conveys no usable information about the tool.

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 nine-parameter tool with no annotations and no output schema, the description is completely inadequate. Nothing explains the parameters, the return value, or the operation, leaving the agent unable to invoke 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?

Schema description coverage is 100%, which normally sets a baseline of 3, but the description contributes nothing to parameter understanding and instead asserts an unrelated conversion behavior that conflicts with every parameter listed.

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 claims a unit conversion (nanometers to meters), but the schema exposes nine unrelated string parameters (ref, url, city, feed, host, json, path, zone, query). It is misleading rather than descriptive and gives no basis for distinguishing this tool from any sibling.

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 when-to-use guidance, no alternatives named, and no context for any of the nine parameters. An agent has no way to know when this tool should be selected.

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