Attach a new (or existing) billing plan to a contract.
JWT bearer token obtained from POST /auth/system-login using your client credentials.
Contract ID
Use PlanId or planId to reuse an existing billing plan. If neither is sent, the route creates a new plan and expects name, and typically items.
"100"
"2026-04-01"
"100"
"Annual Enterprise Subscription 2026"
"2027-03-31"
standard, extension, renewal "standard"
0
"42"
"42"
When creating a new plan item, provide CurrencyId, PlanTypeId, config, and either SkuId or Sku. The route persists meter references from config.meter and config.quantityMeter.