Do not assume an Ecwid request has a harmless test-mode switch. The official first-request guide says the API has no test mode and recommends a separate store for testing.
For the Ecwid API discussion, distinguish the REST integration's secret access token from a public storefront token. Keep privileged credentials server-side and verify the store ID before any write.
Start with reading a known test product, then make a reversible change in that separate store. Confirm both the returned resource and the visible result before connecting the integration to a live catalog.
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