> ## Documentation Index > Fetch the complete documentation index at: https://docs.mountthor.com/llms.txt > Use this file to discover all available pages before exploring further. # Get costs > Returns itemized costs for a period, priced per machine class. Requires the `billing:GetBillingCosts` permission. ## OpenAPI ````yaml /api-reference/openapi/billing.json get /billing/v1/costs openapi: 3.0.3 info: title: Mount Thor Billing API version: 15089fd70390 description: >- Read your billing account, funds, credits, prices, usage, costs and invoices. Amounts are exact: `units` whole currency units plus `nanos` billionths, never floating point. servers: - url: https://customer-api.mountthor.com security: - bearerAuth: [] paths: /billing/v1/costs: get: summary: Get costs description: |- Returns itemized costs for a period, priced per machine class. Requires the `billing:GetBillingCosts` permission. operationId: CustomerBillingService_GetBillingCosts parameters: - name: period in: query description: '`current` (the current calendar month) or a past month as `YYYY-MM`.' schema: type: string required: true responses: '200': description: OK content: application/json: schema: $ref: '#/components/schemas/GetBillingCostsResponse' '400': description: The request is invalid, for example an unknown query parameter. headers: mt-error-slug: description: A stable, machine-readable error identifier, when one applies. schema: type: string content: application/json: schema: $ref: '#/components/schemas/Error' '401': description: >- The credential is missing, invalid or expired. The response has no body. headers: mt-error-slug: description: A stable, machine-readable error identifier, when one applies. schema: type: string '403': description: >- The credential does not allow this operation. When a permission is missing, `requiredAction` names it; otherwise the body may be empty. headers: mt-error-slug: description: A stable, machine-readable error identifier, when one applies. schema: type: string content: application/json: schema: $ref: '#/components/schemas/Error' components: schemas: GetBillingCostsResponse: type: object properties: period_start: type: string description: >- Start of the period covered (inclusive). The period ends at `period_end`, never later than now. format: date-time period_end: type: string format: date-time requested: type: string description: The canonicalized requested period (`current` or `YYYY-MM`). line_items: type: array items: $ref: '#/components/schemas/BillingCostLineItem' description: Itemized lines, meter-ordered for stable client rendering. total: allOf: - $ref: '#/components/schemas/Money' description: Sum of `amount` across all priced lines. Error: type: object properties: code: type: integer description: A numeric status code. message: type: string description: A human-readable explanation. reason: type: string description: On a 403 from a missing permission, `permission_denied`. requiredAction: type: string description: >- On a 403 from a missing permission, the permission the request needs. BillingCostLineItem: type: object properties: meter: type: string description: The rating meter this line aggregates. resource_kind: type: string description: >- `host` for a paid window (taken from the reservation, not the meter), or `bm`/`vm` parsed from a metered meter. Empty for non-compute meters. resource_class: type: string description: The priced SKU (the machine class), parsed from the meter. quantity_seconds: type: string description: Billable seconds aggregated for this line over the window. unit_price: allOf: - $ref: '#/components/schemas/Money' description: >- Price per machine-hour. For a paid compute window, the rate actually charged; unset when the line has no price. amount: allOf: - $ref: '#/components/schemas/Money' description: >- The line amount. For a paid-window line this is the sum of the ORIGINAL quotes (never recomputed, so it may not equal `quantity_seconds * unit_price`); for a metered line it follows the per-hour rule above. Zero when `!priced`. priced: type: boolean description: >- Whether the line carries a charge. Metered usage with no price for its class is shown unpriced. description: >- Costs for one meter over the period. Lines for paid compute windows carry the amount actually charged; `priced` is false for metered usage with no price. Money: type: object properties: currency_code: type: string description: ISO-4217 currency code, e.g. "USD". units: type: string description: Whole units of the amount. May be negative. nanos: type: integer description: >- Fractional units in nanos (10^-9). For a positive amount, nanos is in [0, 999999999]; units and nanos must share sign. format: int32 description: >- Money — an exact monetary amount. Never use floating point for money; this mirrors the google.type.Money shape (units + nanos + ISO-4217 currency). securitySchemes: bearerAuth: type: http scheme: bearer description: >- Send `Authorization: Bearer ` to https://customer-api.mountthor.com. People use the session that `mthr login` stores (a token starting `mt_session_`, valid for up to 12 hours). Automation uses a service-account credential (starting `mt_sa_v1_`, valid for 90 days) from Create credential. Each operation names the permission it needs. Service accounts hold permissions through custom roles, and some operations refuse them; those operations say so. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.