Domain Presets

Documents have different visual grammars. A price list uses currency baselines, a specification sheet uses key-value colon attributes, and an inventory manifest tracks SKUs and counts.

afferent provides built-in domain presets and supports custom options via SpatialEngineOptions.

Built-In Presets

Price Lists (presets.priceList)

Configured for catalogs, menus, and service rate sheets with currency values:

import { processPageLayout, presets } from "afferent";

const layout = await processPageLayout(lines, presets.priceList);

• Pairs currency symbols ($, USD, €, £) and prices with titles.
• Merges price ranges (e.g. $500 - $1,200).
• Prevents section headers (like GENERAL SERVICES) from absorbing into items.

Technical Spec Sheets (presets.specSheet)

Configured for hardware specifications, datasheets, and technical parameters:

import { processPageLayout, presets } from "afferent";

const layout = await processPageLayout(lines, presets.specSheet);

• Pairs colon-delimited properties (e.g. Operating Voltage: 24V DC).
• Extracts measurement units (mm, kg, W, MHz, RPM).
• Treats component headers (DIMENSIONS, ELECTRICAL, WARRANTY) as section boundaries.

Inventory Manifests (presets.inventory)

Configured for warehouse manifests, parts lists, and logistics tables:

import { processPageLayout, presets } from "afferent";

const layout = await processPageLayout(lines, presets.inventory);

• Matches alphanumeric SKUs and part numbers (AB-1234, SKU-90210).
• Pairs quantities and stock counts.

Custom Configuration

Supply custom options to tailor the engine to your specific layout needs:

import { processPageLayout, type SpatialEngineOptions } from "afferent";

const options: SpatialEngineOptions = {
  // Prevent custom headers from absorbing into descriptions
  sectionHeaderPatterns: [/^(?:SERVICES|EQUIPMENT|TERMS|DISCLAIMERS)/i],

  // Maximum vertical gap to stitch lines into one description (normalized 0..1)
  maxLineVerticalDistance: 0.045,

  // Y-tolerance for horizontal baseline pairing
  horizontalDeltaY: 0.012,

  // Document context passed to System 1 continuation evaluations
  documentContext: "commercial equipment invoice",

  // Custom extractor for non-currency values (dates, codes, serials)
  extractValue: (text) => {
    const match = text.match(/\b([A-Z]{2}-\d{4})\b/);
    return match ? { value: match[1], raw: match[0] } : null;
  },
};

const layout = await processPageLayout(lines, options);