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

There are no annotations, so the description carries the full burden. It does not state whether inputs are read-only, discarded, validated, or converted; the field-level 'discarded after...' notes cannot compensate because the top-level behavior is unclear.

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?

At six words it is under-specified, not concise; the fragment 'number discarded' is ungrammatical and does not earn its place. A useful one-sentence description would need to be longer.

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 tool with 10 optional parameters, no output schema, and no annotations, the description explains almost nothing about inputs, outputs, or selection criteria. It is inadequate for correct invocation.

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 coverage is 100%, so per the rubric the baseline is 3. The description adds no parameter meaning — it neither maps 'nits' or 'number discarded' to any of the ten string parameters nor clarifies their roles.

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 is a sentence fragment about converting nits to cd/m2, which at best restates the tool name and does not mention any of the 10 string inputs or what operation is performed on them. An agent cannot tell what this tool does or how it relates to sibling tools like normalize-url or validate-json.

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 invoke this tool versus any sibling. It names no alternatives, conditions, or exclusions, so an agent must guess based on the unrelated parameter list.

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