> This page is for Developer.

> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.bigcommerce.com/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.bigcommerce.com/_mcp/server.

## Carts API: documented overridable fields for line items

The [Create a Cart](/developer/api-reference/rest/admin/management/carts/carts-single/create-cart) and [Add Cart Line Items](/developer/api-reference/rest/admin/management/carts/items/add-cart-line-items) endpoints now include an **Overridable fields** table that explicitly lists the catalog values you can override when adding line items to a cart.

* **`list_price`** — override the product's price (with a note on promotion eligibility)
* **`name`** — override the product name for locale-specific display
* **`option_selections.name`** — override an option or modifier label
* **`option_selections.value`** — override an option or modifier value

A new request example on the Add Cart Line Items endpoint demonstrates using price, name, and locale-specific option overrides together.

For details, see [Add Cart Line Items](/developer/api-reference/rest/admin/management/carts/items/add-cart-line-items).