{ "openapi": "3.1.1", "info": { "title": "Color Converter \u0026 Gamut Mapper (OKLCH, Lab, P3) API", "version": "1.0.0", "summary": "Convert any CSS color to HEX, RGB, HSL, Lab, LCH, OKLab, OKLCH and Display P3.", "description": "Every endpoint performs the same calculation as the human page and returns inputs, result, units, assumptions, sources, warnings and computedAt. MCP endpoint: /mcp." }, "servers": [ { "url": "https://luminacolorconverter.usefulweb.app" } ], "paths": { "/api/v1/calculate": { "post": { "operationId": "calculate", "summary": "Convert any CSS color to HEX, RGB, HSL, Lab, LCH, OKLab, OKLCH and Display P3.", "description": "Paste a HEX code, CSS named color or any CSS Color 4 function. Get every color space, sRGB and Display P3 gamut checks, the CSS gamut-mapped HEX instead of naive clipping, WCAG contrast against white and black, and the nearest CSS named colors by CIEDE2000.\n\nMethodology:\n- Parse the color with CSS Color 4 syntax: HEX (3, 4, 6 or 8 digits), the 148 named colors, rgb(), hsl(), hwb(), lab(), lch(), oklab(), oklch() and color() with srgb, srgb-linear, display-p3, a98-rgb, prophoto-rgb, rec2020, xyz-d50 and xyz-d65. The keyword none counts as zero.\n- Convert through CIE XYZ (D65) with the matrices of the CSS Color 4 sample code. Lab and LCH use the D50 white with the Bradford adaptation, as in CSS. OKLab and OKLCH follow Ottosson (2020).\n- A color is in a gamut when every encoded channel lies within 0–1 (tolerance 0.000075). Out-of-gamut colors are mapped with the CSS Color 4 binary search: reduce OKLCH chroma at constant lightness and hue until clipping changes the color by less than one just-noticeable difference (deltaEOK 0.02). The plainly clipped HEX is shown for comparison.\n- HSL, HWB, RGB and the WCAG contrast ratios describe the mapped 8-bit sRGB color. Nearest named colors are ranked by CIEDE2000 in CSS Lab.", "tags": [ "apps" ], "x-mcp-tool": "lumina_color_converter", "x-owner-app": "lumina", "requestBody": { "required": true, "content": { "application/json": { "schema": { "$ref": "#/components/schemas/LuminaColorConverterInput" }, "examples": { "example1": { "summary": "A vivid OKLCH green outside sRGB", "value": { "color": "oklch(0.7 0.25 145)", "nearest": 5 } }, "example2": { "summary": "A deep teal HEX code", "value": { "color": "#164E63", "nearest": 3 } }, "example3": { "summary": "A CSS named color", "value": { "color": "rebeccapurple", "nearest": 3 } }, "example4": { "summary": "Display P3 red", "value": { "color": "color(display-p3 1 0 0)", "nearest": 3 } } } } } }, "responses": { "200": { "description": "Calculation result envelope.", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/LuminaColorConverterResult" } } } }, "400": { "description": "Malformed JSON body.", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } }, "422": { "description": "Invalid input (see errors[]).", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } }, "429": { "description": "Rate limit exceeded (see Retry-After).", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } } } } }, "/api/v1/tool": { "get": { "operationId": "getToolDefinition", "summary": "Inputs, output schema and examples for this tool", "responses": { "200": { "description": "Tool definition.", "content": { "application/json": { "schema": { "type": "object" } } } } } } } }, "components": { "schemas": { "Problem": { "type": "object", "description": "RFC 9457 problem details. 422 responses include per-field `errors`.", "required": [ "type", "title", "status", "detail" ], "properties": { "type": { "type": "string" }, "title": { "type": "string" }, "status": { "type": "integer" }, "detail": { "type": "string" }, "code": { "type": "string" }, "errors": { "type": "array", "items": { "type": "object", "required": [ "field", "message" ], "properties": { "field": { "type": "string" }, "message": { "type": "string" } } } } } }, "LuminaColorConverterInput": { "type": "object", "additionalProperties": false, "properties": { "color": { "title": "CSS color (HEX, name, rgb(), hsl(), hwb(), lab(), lch(), oklab(), oklch() or color())", "type": "string", "maxLength": 200, "default": "oklch(0.7 0.25 145)" }, "nearest": { "title": "Nearest CSS named colors to list", "type": "integer", "minimum": 1, "maximum": 10, "default": 5 } }, "required": [] }, "LuminaColorConverterResult": { "type": "object", "additionalProperties": false, "required": [ "schemaVersion", "tool", "computedAt", "inputs", "summary", "result", "units", "assumptions", "sources", "warnings", "presentation", "links" ], "properties": { "schemaVersion": { "type": "string", "const": "1.0" }, "tool": { "type": "object", "additionalProperties": false, "required": [ "id", "name", "version" ], "properties": { "id": { "type": "string" }, "name": { "type": "string" }, "version": { "type": "string" } } }, "computedAt": { "type": "string", "format": "date-time" }, "inputs": { "type": "object", "description": "Normalised inputs actually used, including applied defaults." }, "summary": { "type": "string" }, "result": { "type": "object", "additionalProperties": false, "required": [ "input", "parsedSpace", "alpha", "named", "hex", "clippedHex", "inSrgb", "inDisplayP3", "mappingDeltaEOK", "rgb", "hsl", "hwb", "lab", "lch", "oklab", "oklch", "xyzD65", "xyzD50", "displayP3", "css", "contrastWhite", "contrastBlack", "nearestNamed" ], "properties": { "input": { "type": "string" }, "parsedSpace": { "type": "string" }, "alpha": { "type": "number" }, "named": { "type": [ "string", "null" ] }, "hex": { "type": "string" }, "clippedHex": { "type": "string" }, "inSrgb": { "type": "boolean" }, "inDisplayP3": { "type": "boolean" }, "mappingDeltaEOK": { "type": "number" }, "rgb": { "type": "array", "items": { "type": "integer" }, "minItems": 3, "maxItems": 3 }, "hsl": { "type": "array", "items": { "type": [ "number", "null" ] }, "minItems": 3, "maxItems": 3 }, "hwb": { "type": "array", "items": { "type": [ "number", "null" ] }, "minItems": 3, "maxItems": 3 }, "lab": { "type": "array", "items": { "type": "number" }, "minItems": 3, "maxItems": 3 }, "lch": { "type": "array", "items": { "type": [ "number", "null" ] }, "minItems": 3, "maxItems": 3 }, "oklab": { "type": "array", "items": { "type": "number" }, "minItems": 3, "maxItems": 3 }, "oklch": { "type": "array", "items": { "type": [ "number", "null" ] }, "minItems": 3, "maxItems": 3 }, "xyzD65": { "type": "array", "items": { "type": "number" }, "minItems": 3, "maxItems": 3 }, "xyzD50": { "type": "array", "items": { "type": "number" }, "minItems": 3, "maxItems": 3 }, "displayP3": { "type": "array", "items": { "type": "number" }, "minItems": 3, "maxItems": 3 }, "css": { "type": "object", "additionalProperties": false, "required": [ "hex", "rgb", "hsl", "hwb", "lab", "lch", "oklab", "oklch", "displayP3" ], "properties": { "hex": { "type": "string" }, "rgb": { "type": "string" }, "hsl": { "type": "string" }, "hwb": { "type": "string" }, "lab": { "type": "string" }, "lch": { "type": "string" }, "oklab": { "type": "string" }, "oklch": { "type": "string" }, "displayP3": { "type": "string" } } }, "contrastWhite": { "type": "number" }, "contrastBlack": { "type": "number" }, "nearestNamed": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "name", "hex", "deltaE2000" ], "properties": { "name": { "type": "string" }, "hex": { "type": "string" }, "deltaE2000": { "type": "number" } } } } } }, "units": { "type": "object", "additionalProperties": { "type": "string" } }, "assumptions": { "type": "array", "items": { "type": "string" } }, "sources": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "title" ], "properties": { "title": { "type": "string" }, "url": { "type": "string" }, "publisher": { "type": "string" }, "retrievedAt": { "type": "string" }, "note": { "type": "string" } } } }, "warnings": { "type": "array", "items": { "type": "string" } }, "presentation": { "type": "array", "items": { "type": "object" }, "description": "Display blocks used by the human page (same data)." }, "links": { "type": "object", "additionalProperties": false, "required": [ "human", "api", "openapi", "methodology" ], "properties": { "human": { "type": "string", "format": "uri" }, "api": { "type": "string", "format": "uri" }, "openapi": { "type": "string", "format": "uri" }, "methodology": { "type": "string", "format": "uri" } } } } } } } }