> ## Documentation Index > Fetch the complete documentation index at: https://docs.abbyy.com/llms.txt > Use this file to discover all available pages before exploring further. # Fields tab > Create skill fields, label documents, view predicted labeling, and configure validation rules on the Fields tab in Advanced Designer. On the **Fields** tab, you create skill fields and label documents for a [Document skill](/vantage/documentation/advanced-designer/document-skills/document-skills). The tab has two sections: **Reference**, where you label the correct fields and their locations, and **Predicted**, where the skill's own labeling appears after it runs. Trainable activities like Segmentation and Deep Learning need labeled documents to train. Advanced Designer also compares reference labeling to extraction results when measuring skill quality, so labeling drives both training and testing. ## Edit skills created in Vantage When you edit a skill that was created and labeled in Vantage, its final field structure and labeling appear unchanged in the **Fields** tab. You can refine that labeling, add fields, or change the data form here without losing the work done in Vantage. ## Create skills in Advanced Designer For a skill you build in Advanced Designer, label your documents after uploading them: define every field to extract and mark its location on the image in the **Reference** section. To add a field, click **Add Field** on the toolbar; the field appears on the data form, ready for you to mark its location on the document image. Follow the [labeling guidelines](/vantage/documentation/advanced-designer/labeling/labeling). You can rearrange and resize fields on the data form at any time — see [Editing data form layout](/vantage/documentation/skill-designer/document/adding-fields/editing-data-form-layout). Switch document sets from the drop-down next to the set name. The shortcut menu lets you modify the active set. ## Predicted labeling After a skill runs, the **Predicted** section shows its labeling output. To turn predictions into reference labeling, select the documents and choose **Copy Predicted Labeling to Reference** on the shortcut menu. The same command is available in the activity editors and on the [**Documents**](/vantage/documentation/advanced-designer/document-skills/documents) tab. ## Validation rules Add business-logic rules that compare field values, trigger on field changes, or update other fields. Rules behave the same as in Vantage — see [Rule verification](/vantage/documentation/skill-designer/document/rule-verification/rule-verification). Configure them in the **Reference** section of the **Fields** tab. ### Add a rule Click the **New Rule** button. The dialog that opens lists every existing Vantage rule. Choose the rule type and the fields it should check. To edit or delete a rule, click the more options button next to it. Rules created in Advanced Designer and Vantage are kept in sync. If a skill has local-folder synchronization enabled, rules sync there too. Rules apply to both predicted and reference labeling. ## Related topics Manual and import-based labeling for training a skill. Upload documents and organize them into sets for training and testing. Build the document processing flow.