set_layer_position

Instructions

Implementation Reference

• src/lib/ops-glass.ts:334-380 (handler)

  The actual handler that reads an icon bundle manifest, updates the scale and offset (translation-in-points) for either a group or a specific layer, then saves the manifest.

  export async function setLayerPosition(params: SetLayerPositionParams): Promise<McpResult> {
    try {
      const { manifest } = await readIconBundle(params.bundle_path);
  
      if (manifest.groups.length === 0) {
        return err('Error: No groups in this icon bundle');
      }
  
      const group = manifest.groups[Math.min(params.group_index, manifest.groups.length - 1)];
  
      if (params.target === 'group') {
        const currentPos = group.position ?? { scale: 1.0, 'translation-in-points': [0, 0] as [number, number] };
        group.position = {
          scale: params.scale ?? currentPos.scale,
          'translation-in-points': [
            params.offset_x ?? currentPos['translation-in-points'][0],
            params.offset_y ?? currentPos['translation-in-points'][1],
          ],
        };
      } else {
        const layerIdx = params.layer_index ?? 0;
        if (layerIdx >= group.layers.length) {
          return err(`Error: Layer index ${layerIdx} out of range (group has ${group.layers.length} layers)`);
        }
        const layer = group.layers[layerIdx];
        const currentPos = layer.position ?? { scale: 1.0, 'translation-in-points': [0, 0] as [number, number] };
        layer.position = {
          scale: params.scale ?? currentPos.scale,
          'translation-in-points': [
            params.offset_x ?? currentPos['translation-in-points'][0],
            params.offset_y ?? currentPos['translation-in-points'][1],
          ],
        };
      }
  
      await saveManifest(params.bundle_path, manifest);
  
      const targetDesc = params.target === 'group'
        ? `group ${params.group_index}`
        : `layer ${params.layer_index ?? 0} in group ${params.group_index}`;
  
      return ok(`Updated position on ${targetDesc}: scale=${params.scale ?? '(unchanged)'}, offset=(${params.offset_x ?? '(unchanged)'}, ${params.offset_y ?? '(unchanged)'})`);
    } catch (error: unknown) {
      const msg = error instanceof Error ? error.message : 'Unknown error';
      return err(`Error: ${msg}`);
    }
  }

• src/lib/ops-glass.ts:70-78 (schema)

  TypeScript interface defining the input parameters for set_layer_position.

  export interface SetLayerPositionParams {
    bundle_path: string;
    target: 'layer' | 'group';
    group_index: number;
    layer_index?: number;
    scale?: number;
    offset_x?: number;
    offset_y?: number;
  }

• src/server.ts:207-221 (registration)

  Registers the tool with the MCP server using the name 'set_layer_position', defines Zod schema for input validation, and delegates to the handler function.

  // ── Tool: set_layer_position ──
  server.tool(
    'set_layer_position',
    'Set the scale (zoom) and offset of a layer or group within the .icon bundle. Use to zoom the glyph in/out or reposition it.',
    {
      bundle_path: z.string().describe('Path to .icon bundle'),
      target: z.enum(['layer', 'group']).default('layer').describe('Whether to set position on a layer or group'),
      group_index: z.number().default(0).describe('Group index (0-based)'),
      layer_index: z.optional(z.number()).describe('Layer index within the group (0-based, required for target=layer)'),
      scale: z.optional(z.number().min(0.05).max(3.0)).describe('Scale factor (0.05-3.0, where 1.0 = full size, 0.5 = half, 2.0 = double)'),
      offset_x: z.optional(z.number()).describe('X offset in points'),
      offset_y: z.optional(z.number()).describe('Y offset in points'),
    },
    async (params) => setLayerPosition(params),
  );