> ## Documentation Index > Fetch the complete documentation index at: https://documentation.qonversion.io/llms.txt > Use this file to discover all available pages before exploring further. # Offerings > Bundles of products shown to users in paywalls An **Offering** is a named bundle of products that the SDK consumes to render a paywall or purchase flow. Offerings decouple the products a user sees from the product IDs in your app code — you can change the contents of an offering without shipping a new build. At most one offering per project is marked as the **main** offering and is returned to the SDK by default when no specific id is requested. ## Key concepts * **Offering ID** — Stable identifier you choose (e.g., `onboarding`, `winback`). Used in the API path and in related resources (experiments, scheduled reports). Up to 64 characters; allowed characters are `a–z`, `A–Z`, `0–9`, `.`, `_`, `-`, `:`, and spaces. Immutable after create. * **Products** — An ordered list of product UIDs attached to the offering. The SDK renders them in the order you define. Each UID must already exist in the same project; product UIDs are up to 255 characters from the same charset as offering ids. * **Main offering** — At most one offering per project carries `tag: 1`. Use `POST /v4/offerings/{offering_id}/set-main` to switch the main — it atomically clears the previous main inside a single transaction. `tag=1` on `POST /offerings` and `PATCH /offerings/{id}` is rejected with `400` (typed code `cannot_set_main_directly`). To make an offering the project's main, create or patch it without `tag` and call `POST /offerings/{id}/set-main` afterward — that endpoint flips the main flag atomically. Patching the project's current main offering with `tag: 0` (or any non-main value) is rejected with `422` (typed code `cannot_demote_main`). To switch which offering is main, call `POST /offerings/{new-main-id}/set-main` — the previous main is cleared in the same transaction. * **Tag** — On read: `1` = main offering, `0` = regular offering previously demoted from main, `null` = regular offering that has never been tagged. Treat `0` and `null` as equivalent on read. Tag is read-only via `PATCH`; use `set-main` to promote and `set-main` on a different offering to implicitly demote the current main. On `POST` only `0` and `null` are accepted (and `tag=1` is rejected as above). The very first offering created in an empty project is auto-promoted to `tag: 1` even if `tag` is omitted in the request. * **Experiment-variant offerings** — Offerings owned by the experiments service are excluded from `GET /offerings` and return `404` from `GET /offerings/{offering_id}`. `PATCH`, `DELETE`, and `set-main` on an experiment-variant id return `422` with typed codes `cannot_patch_experiment_variant`, `cannot_delete_experiment_variant`, and `cannot_setmain_experiment_variant` respectively. ## Offering object | Field | Type | Description | | ------------- | --------------- | ------------------------------------------ | | `object` | string | Always `offering`. | | `id` | string | Offering identifier. | | `url` | string | Canonical API path (`/v4/offerings/{id}`). | | `tag` | integer \| null | `1` = main, `0` or `null` = regular. | | `product_ids` | string\[] | Product UIDs in display order. | | `created_at` | string | ISO 8601 UTC creation timestamp. | | `updated_at` | string | ISO 8601 UTC last-update timestamp. | ## Available endpoints | Method | Endpoint | Description | Status | | ------ | ----------------------------------- | ------------------------------------------------- | ------ | | GET | `/offerings` | List offerings | New | | POST | `/offerings` | Create an offering | New | | GET | `/offerings/{offering_id}` | Get an offering | New | | PATCH | `/offerings/{offering_id}` | Update an offering (partial) | New | | DELETE | `/offerings/{offering_id}` | Delete an offering | New | | POST | `/offerings/{offering_id}/set-main` | Mark this offering as the project's main offering | New | `PATCH` replaces `product_ids` with the supplied list — pass `[]` to detach all products, or omit the field to leave the list unchanged. ## Authentication All v4 endpoints require a **Secret Key**. See [Authentication](/reference/v4/authentication). ## Errors The Offerings API follows the standard error envelope and codes documented on [Handling Errors](/reference/v4/handling-api-errors). | Code | HTTP | Description | | ----------------------------------- | ---- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `not_found` | 404 | Offering does not exist in this project, or the id belongs to an experiment-variant offering filtered out by `GET`. | | `offering_already_exists` | 409 | `POST /offerings` was called with an `id` that already exists in this project. | | `product_not_in_project` | 400 | `product_ids` references a product UID that is not registered in the project. | | `cannot_set_main_directly` | 400 | `tag: 1` was sent on `POST /offerings` or `PATCH /offerings/{id}`. Call `POST /offerings/{id}/set-main` instead. | | `cannot_demote_main` | 422 | `PATCH /offerings/{id}` tried to set `tag: 0` (or any non-main value) on the project's current main offering. Promote a different offering via `set-main` to switch instead. | | `cannot_patch_experiment_variant` | 422 | `PATCH /offerings/{id}` was called against an offering owned by the experiments service. | | `cannot_delete_experiment_variant` | 422 | `DELETE /offerings/{id}` was called against an offering owned by the experiments service. | | `cannot_setmain_experiment_variant` | 422 | `POST /offerings/{id}/set-main` was called against an offering owned by the experiments service. |