Adjust a shipping rate
Authorizations
A secret API key. Publishable keys cannot reach this API. A key may carry an expiry, and an expired key is refused exactly like an unknown one, with a 401 that names no reason; check the key's expires_at in the dashboard rather than inferring it from a response. When a merchant rolls a key's secret they choose a grace window of up to 3 days, and for its duration BOTH the new secret and the one it replaced authenticate, so an integration moves over on its own deploy schedule instead of at the instant the button is pressed. Move before the window closes: after it, the old secret is refused. Nothing else about this contract moves with a roll. The key keeps its id and its scopes, so the only thing an integration updates is the credential itself.
Headers
A unique key per logical write. Replaying a request with the same key returns the first response byte for byte instead of applying the write twice.
Path Parameters
Body
An omitted key keeps its stored value, which is what a rate adjustment is: one number moves and the rest stays as the merchant left it. An EMPTY body is refused rather than treated as a no-op, because the merge still writes the row and would move updated_at, which is the field this resource publishes so you can sync incrementally.
Non-blank. Omit the key to leave it unchanged.
0 <= x <= 1000000000000false stops checkout offering the rate and is fully reversible. It is what to use instead of the DELETE, which needs a second grant.
Three states. Omit the key to leave the binding alone; send null to CLEAR it and make the rate global again; send an id to bind it. An empty string is refused, because it could mean either and guessing wrong offers one region's rate at every destination on earth.
Response
Success
