color_contrast_ratio

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

No annotations are provided, and the description does not disclose any behavioral traits. It does not explain that the contrast ratio is typically related to WCAG accessibility standards, nor does it mention return format, limitations, or side effects. The tool is treated as a black box.

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 concise with a single sentence, which is efficient for a simple operation. However, it sacrifices completeness for brevity. It is front-loaded with the action immediately.

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?

Given the lack of output schema, the description should at least hint at the return value (e.g., a numeric ratio, passes/fails thresholds). It also lacks any context about color spaces or usage scenarios. The tool is simple but the description is insufficient for an agent to fully understand the tool's behavior.

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 0%, yet the description adds no information beyond the parameter names (foreground, background). It does not explain that these are expected to be color values in formats like hex, RGB, etc., nor does it provide format requirements or constraints.

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 action ('Check') and the resource ('contrast ratio between two colors'). It distinguishes this tool from siblings like color_convert, color_info, color_mix, and color_palette by using the specific term 'contrast ratio', which is a distinct operation.

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 provided about when to use this tool versus alternatives. There are no hints about prerequisites, such as needing to know color formats, or when not to use it. The description is a single sentence with no usage context.

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