An API (application programming interface) is a door through which a program, rather than a person, talks to your marketplace. What you do by hand in the admin panel, a program can do through the API, as often as needed.
What it is used for
- Connect your management software: send each new order to your ERP or accounting tool, keep stock in step with a warehouse.
- Import or update a catalogue: create hundreds of listings from a spreadsheet or a supplier’s catalogue.
- Build a mobile app or your own storefront: your users sign in, browse, order and follow their orders from an app.
- Let a seller connect their own system: their catalogue and orders stay in step with the tool they already use.
- Keep your own data on objects: store an external reference on a user, a listing or an order (a metafield).
The three APIs
| API | Who it acts for | Typical use |
|---|---|---|
| Admin API | You, the administrator: it sees the whole marketplace | Your ERP, CRM or accounting tool, catalogue imports, automation |
| Front API | One user, seller or buyer, signed in with their email and password | A mobile app, a storefront you build yourself |
| Partners API | One seller: it only sees their listings and orders | A seller’s stock, order or warehouse software |
Admin API. It acts with the rights of an administrator, so it is used from a server, never from a page your users load. Each administrator generates their own key and secret: see Get your Admin API keys.
Front API. A user signs in from the app with their own email and password; there is no key to generate.
Partners API. There is no screen to generate its access: it is issued on request, for a given seller. Contact Kreezalid support with your marketplace and the seller’s account.
Be told when something changes
Rather than asking the API every few minutes whether a new order has arrived, a program can be told: a webhook sends a message to a URL of your choice as soon as a user, a listing or an order changes. See Webhooks on the developer hub.
Where developers find the documentation
The developer hub describes every API: the quickstart, the authentication, the full reference of each request, and step-by-step guides (importing a catalogue, sending orders to an ERP, building a mobile app).
To try a request yourself without writing code, see Test the Admin API with an API client.
What your users see
Nothing changes for sellers and buyers while you only use the API from your own tools. What a program creates or changes through the API (a listing, a page, an order status) then appears on the storefront and in their account as if you had done it in the admin panel.
Edge cases and limits
- A connected custom domain: the APIs answer on your marketplace’s main domain, which is your custom domain once it is connected. A program that calls the
mykreezalid.comURL receives a redirect, which many programs do not follow. - No access rights per key: an Admin API key can do everything an administrator can do. Keep it in your developer’s hands only.
- Usage is measured: Settings › API usage shows the calls made to your marketplace, per API. Traffic that harms the marketplace can be slowed down or refused.
- An AI agent such as ChatGPT or Claude does not use these keys: it connects through MCP, with the permissions you grant it. See Connect an AI agent to your marketplace with MCP.