Google, Meta, Microsoft and most other channels want each product to have a product category from Google's list of categories, e.g. Apparel & Accessories > Clothing > Shirts & Tops. The channel's Categories tab helps you set it for all your products at once. Feedsmith puts the result in the channel's category field, which is google_product_category.
The custom channel has no category field, so it shows "This channel has no category field".
For each product, Feedsmith tries three things in order and uses the first one that gives a category.
If one of these gives a category, it replaces whatever your mapping put in google_product_category. If none of them does, the mapping's value is kept.
The Default category is used for every product that no rule or group gives a category to. For example, a shop that only sells clothing might use Apparel & Accessories > Clothing. Leave it empty if you don't want a default.
Auto lets you give a category to every product with the same value in a field.
product_type.T-Shirts (240 products) and Jackets (85 products).shirts.Use the All, Assigned and Missing filters to find groups without a category, and Search groups to find one group. A group's value has to match the product's value exactly, so if you rename a product type in your store, assign the new name too.
Manual rules give a category to products that match conditions. They run before Auto, so they win.
tags includes rain. See Conditions.For example, the rule "Apparel & Accessories > Clothing > Outerwear > Coats & Jackets if title includes jacket" puts every jacket in that category, even when its product type is assigned something else under Auto.
Manual rules can use source fields and global store fields, but not channel fields.
When you search, Feedsmith shows matching categories from Google's list, with each category's ID and full name. Results whose last part matches your words come first, and you can also search by ID, e.g. 212. When you pick a category, Feedsmith uses its full name, e.g. Apparel & Accessories > Clothing > Shirts & Tops. To use text that isn't in the list, click Use "your text".