> For the complete documentation index, see [llms.txt](https://apidocs.akinon.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://apidocs.akinon.com/commerce-openapis/search/introduction/facet-field-retrieval.md).

# Facet Field Retrieval

Facet fields are retrieved from Elasticsearch before product results. The retrieval process:

1. **Facet Configuration**: If a Facet Configuration exists for an attribute, it determines the facet's aggregation settings, field mappings, and extraction strategy
2. **Size Limits**:
   * If attribute key is "category\_ids", size is set to 500
   * Otherwise, default size is 100
   * Custom sizes can be configured via Facet Configuration
3. **Inventory Strategy Context**: Facet fields are returned with inventory strategy context, as prices and availability may vary by inventory strategy
4. **Widget Creation**: After retrieval, facet data is converted to widgets:
   * Attribute IDs from Elasticsearch are used to fetch attribute values from the database
   * Widget types are determined by attribute configuration
   * Widgets include choices with quantities, labels, and selection states


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