Official MCP RegistryListed
Swatch
Check WCAG color contrast, fix failing colors, build 50-950 palettes. No account.
First seen 2 Nov 2026. Evidence as of 4 Nov 2026.
6
Tools
From an anonymous probe
1
Source listings
Each with its own history
2
Recorded changes
Since first seen
Tools
| Tool | Description | Behaviour |
|---|---|---|
| swatch_check_contrast | Use when the user asks whether a color combination is readable or accessible, passes WCAG AA or AAA, or has enough contrast (text on a background, button, badge, link color). Returns the exact contrast ratio, pass or fail for normal text, large text and UI components at AA and AAA, the APCA lightness contrast and a plain note. Colors can be hex, rgb(), hsl() or CSS names. Example: {"foreground": "#777777", "background": "#ffffff"}. Language models cannot compute this reliably, so call it instead of guessing. | Read-only |
| swatch_check_pairs | Use when the user has a whole design system, theme or stylesheet and wants every text and background pair checked for accessibility in one go. Takes up to 50 pairs and returns the ratio and AA and AAA results for each, with a count of failures. Example: {"pairs": [{"foreground": "#777", "background": "#fff", "label": "muted text"}, {"foreground": "#fff", "background": "#ff5a1f", "label": "button"}]}. | Read-only |
| swatch_convert_color | Use when the user asks to convert a color between hex, RGB, HSL and OKLCH, or asks what a color is called or how light it is. Returns all formats, the relative luminance and the nearest CSS color name. Example: {"color": "#ff5a1f"}. Exact math, so prefer it to converting by hand. | Read-only |
| swatch_fix_contrast | Use when a color pair fails contrast and the user wants the smallest change that makes it pass, such as "make this gray text accessible without changing the look". Returns the closest text color on that background that reaches the target (AA, AAA, AA-large or ui), and separately the closest background, keeping the hue. Example: {"foreground": "#777777", "background": "#ffffff", "target": "AA"}. Returns already_passes if nothing needs to change. | Read-only |
| swatch_make_scale | Use when the user asks for a palette, shades, tints, a design-token scale or a Tailwind-style 50 to 950 ramp from a brand color. Returns 11 steps that keep the hue, with the hex, contrast on white and on black, and the best text color for each step. Example: {"color": "#ff5a1f", "name": "brand"}. | Read-only |
| swatch_pick_text_color | Use when the user asks what text color (black or white) to put on a given background, button or brand color so it is readable. Returns the better of black or white with both contrast ratios, the WCAG grade and a softer near-black option. Example: {"background": "#ff5a1f"}. | Read-only |
Change history
- server instructions changed (+"Results include a link (open_url) that the user can open" +"see the same result on" +"website.")
- Listed (registry)
| Source | Listing | First seen | Last seen | Versions |
|---|---|---|---|---|
| Official MCP Registry | com.clawhard/swatch | 2 Nov 2026 | 4 Nov 2026 | 1 |