search_inks_by_color
Find fountain pen inks matching a specific color by entering a hex code to discover similar shades from the database.
Instructions
Find inks similar to a given color using RGB matching
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| color | Yes | Hex color code (e.g., "#FF5733") | |
| max_results | No | Maximum number of results to return (default: 20) |
Implementation Reference
- src/index.ts:364-394 (handler)The primary handler function for the 'search_inks_by_color' tool. Converts input hex color to RGB, finds closest matching inks using color distance, retrieves metadata, formats results as JSON, and returns MCPTextResponse.
private searchInksByColor(colorHex: string, maxResults: number): MCPTextResponse { try { const targetRgb = hexToRgb(colorHex); const closestInks = findClosestInks(targetRgb, this.inkColors, maxResults); const results: SearchResult[] = closestInks.map((ink) => { const metadata = this.getInkMetadata(ink.ink_id); return createSearchResult(ink, metadata, ink.distance); }); return { content: [ { type: 'text', text: JSON.stringify( { target_color: colorHex, target_rgb: targetRgb, results_count: results.length, results, }, null, 2, ), }, ], } satisfies MCPTextResponse; } catch { throw new Error(`Invalid color format: ${colorHex}. Please use hex format like #FF5733`); } } - src/index.ts:159-177 (schema)Tool schema definition in the ListTools response, specifying input parameters: color (required hex string) and optional max_results.
{ name: 'search_inks_by_color', description: 'Find inks similar to a given color using RGB matching', inputSchema: { type: 'object', properties: { color: { type: 'string', description: 'Hex color code (e.g., "#FF5733")', }, max_results: { type: 'number', description: 'Maximum number of results to return (default: 20)', default: 20, }, }, required: ['color'], }, }, - src/index.ts:277-281 (registration)Dispatch registration in the CallToolRequestSchema handler switch statement, mapping tool calls to the searchInksByColor method.
case 'search_inks_by_color': return this.searchInksByColor( args.color as string, (args.max_results as number) || 20, ); - src/utils.ts:106-120 (helper)Core helper function that computes Euclidean RGB color distances for all inks against target, sorts by closeness, and returns top matches with distance.
export function findClosestInks( targetRgb: [number, number, number], inkColors: InkColor[], maxResults: number = 20, ): InkWithDistance[] { const distances = inkColors.map((ink) => ({ ...ink, distance: calculateColorDistance(targetRgb, ink.rgb), // Now both are RGB! })); // Sort by distance (closest first) distances.sort((a, b) => a.distance - b.distance); return distances.slice(0, maxResults); } - src/utils.ts:15-27 (helper)Utility function to parse hex color string to RGB array, used in the handler for input validation and conversion.
export function hexToRgb(hex: string): [number, number, number] { const cleanHex = hex.replace(/^#/, ''); if (cleanHex.length !== 6) { throw new Error('Invalid hex color string'); } const bigint = parseInt(cleanHex, 16); const r = (bigint >> 16) & 255; const g = (bigint >> 8) & 255; const b = bigint & 255; return [r, g, b]; }