Osello has a full JSON API for developers and agencies who want to build on top of the platform. The complete, interactive reference lives at osello.com/api-docs.
What the API can do
The Osello app itself runs on this API, so most of what you can do in the app, a program can do too:
- Products — create, read, and update your products, variants, images, and metafields.
- Listings — read your listings and variants, edit their field values, and submit them to a marketplace.
- Marketplaces — browse each marketplace's categories, fields, and the options each field accepts.
- Offers, inventory, and pricing — manage inventory locations and stock levels, and read the offers each marketplace receives.
- Orders — list marketplace orders, accept them, fulfill them with tracking, and handle returns.
The reference covers the endpoints we support for outside integrations. Some app features — AI
prompts, spreadsheet imports and exports, and account administration — aren't part of it; if you
need one of those in an integration, get in touch.
Where the documentation lives
Everything is documented at osello.com/api-docs:
- Browse every endpoint with its parameters, example requests, and example responses.
- Download the full OpenAPI specification, which works with code generators and API clients.
How authentication works
Every API request must include an access token in the Authorization header:
Authorization: Bearer <your-access-token>
Tokens are tied to an Osello user account, so API requests can see and change the same stores that user manages.
There's currently no page in the app for creating API keys yourself. To get set up with API access, contact us or click the Get Help button in the app — tell us what you're building and we'll get you the credentials you need.
Good to know
- The API speaks JSON over HTTPS against
app.osello.com. - Records are identified by short prefixed IDs returned by the API — use them when reading or updating specific products, listings, or orders.
- Not a developer? You may not need the API at all: spreadsheet imports and exports cover most bulk-editing needs without writing any code.