# Create a rate plan version (/api/usage-rate-plans/create-usage-rate-plan)

`POST https://api.comecero.com/api/v1/usage/rate_plans`

Prices a metric. A saved version never changes: to change a price, save a new `version` with the same `rate_plan_id`. Tiers and package sizes price only the units above the included allowance. Secret and trusted tokens may call it; a limited token may not (`403`). The plan is not checked against an agreement's currency here: use a plan in the agreement's currency, or its billing run fails with `currency_mismatch`.

Request body: the `usage_rate_plan_request` schema.

Responses: 201, 400, 401, 403, 404, 409, 500.

Full schemas: operation `create_usage_rate_plan` in /openapi.json.