Generate Border Radius Scale

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

Annotations already mark the operation as read-only and idempotent. The description adds valuable behavioral details beyond annotations: it specifies that output includes 6 levels, px/rem values, usage guidance, and CSS custom properties. This gives the agent a clear picture of what to expect without contradicting the annotations.

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 well-structured with short paragraphs for arguments, return value, and examples. Every sentence contributes: the purpose, style definitions, parameter details, output summary, and two usage examples. It is comprehensive yet succinct with no filler.

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?

Despite having no output schema, the description clearly explains the return contents (scale levels, units, guidance, CSS variables). With only two optional parameters and clear parameter documentation, plus annotations covering safety, the description is sufficient for an agent to invoke and interpret results 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?

The input schema provides minimal descriptions for both parameters ('Radius visual style' and 'Output format'), but the description enriches them by explaining the meaning of each style enum ('sharp (minimal radius)', 'subtle (small radius)', etc.) and covering defaults. This goes beyond the schema, adding genuine semantic value despite high schema coverage.

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 clearly states the tool's function: 'Generate a border-radius scale with named levels'. It identifies the specific resource (border radius) and action (generate), and the mention of styles like sharp, subtle, rounded, pill distinguishes it from sibling UI generation tools such as color palettes or typography.

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?

The description provides clear context for when to use this tool (when needing a border-radius scale), and it gives examples for style choices. However, it does not explicitly state when not to use it or name alternative tools for other design needs, so it falls short of a perfect score.

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