> ## Documentation Index > Fetch the complete documentation index at: https://commet.co/docs/llms.txt > Use this file to discover all available pages before exploring further. # Track usage event > Track a usage event for a metered feature. Deducts from balance/credits if applicable. Track a usage event for a metered feature. Deducts from balance/credits if applicable. ## OpenAPI ````yaml /openapi/es/rest/2026-08-27.json post /usage/events openapi: 3.1.0 info: title: Commet API version: '2026-08-27' description: Billing and payments API for SaaS and AI products. servers: - url: https://commet.co/api/v1 security: - ApiKeyAuth: [] tags: - name: Test Clock description: >- Simulate the passage of time in sandbox to test billing flows. Mirrors Stripe test clocks: forward-only and sandbox-only. - name: Customers - name: Subscriptions - name: Plans - name: Markets description: >- Reusable country groups for market-specific prices and selectable price variants. - name: Offers - name: Promo Codes - name: Features - name: Usage - name: Seats - name: Quota - name: Add-ons - name: Portal - name: Credit Packs - name: Plan Groups - name: Invoices - name: Payments description: >- One-time payments with no subscription or plan. Charge a customer's saved payment method off-session, or create a payment link the customer opens to pay. Tax, invoice, and receipt are handled automatically. - name: Transactions - name: Webhooks - name: API Keys - name: Payouts description: >- Withdraw available balance to your bank and manage the payout account (verification + destination bank accounts). - name: Provisioning description: >- Take ownership of an organization an agent provisioned headlessly. The agent holds the API keys from the start; a human claims the account through a claim link. paths: /usage/events: post: tags: - Usage summary: Track usage event description: >- Track a usage event for a metered feature. Deducts from balance/credits if applicable. operationId: track-usage parameters: - name: Idempotency-Key in: header required: false description: >- Unique key used to safely retry this write for 24 hours without applying it twice. schema: type: string minLength: 1 maxLength: 200 - name: Commet-Version in: header required: false description: >- API version used by this reference. Send this header to select this contract explicitly. schema: type: string default: '2026-08-27' example: '2026-08-27' requestBody: required: true content: application/json: schema: oneOf: - type: object properties: featureCode: type: string minLength: 1 maxLength: 50 pattern: ^[a-z0-9_]+$ customerId: type: string minLength: 1 maxLength: 200 eventId: type: string minLength: 1 maxLength: 200 timestamp: type: string format: date-time properties: default: [] type: array items: type: object properties: property: type: string minLength: 1 maxLength: 100 value: type: string minLength: 1 maxLength: 1000 required: - property - value model: type: string minLength: 1 maxLength: 200 inputTokens: type: integer minimum: 0 maximum: 9007199254740991 outputTokens: type: integer minimum: 0 maximum: 9007199254740991 value: not: {} cacheReadTokens: type: integer minimum: 0 maximum: 9007199254740991 cacheWriteTokens: type: integer minimum: 0 maximum: 9007199254740991 required: - featureCode - customerId - model - inputTokens - outputTokens additionalProperties: false - type: object properties: featureCode: type: string minLength: 1 maxLength: 50 pattern: ^[a-z0-9_]+$ customerId: type: string minLength: 1 maxLength: 200 eventId: type: string minLength: 1 maxLength: 200 timestamp: type: string format: date-time properties: default: [] type: array items: type: object properties: property: type: string minLength: 1 maxLength: 100 value: type: string minLength: 1 maxLength: 1000 required: - property - value value: default: 1 type: number minimum: 0 model: not: {} inputTokens: not: {} outputTokens: not: {} cacheReadTokens: not: {} cacheWriteTokens: not: {} required: - featureCode - customerId additionalProperties: false responses: '201': description: Success headers: X-Request-Id: $ref: '#/components/headers/RequestId' RateLimit-Limit: description: Maximum number of requests allowed in the current window. schema: type: string RateLimit-Remaining: description: Requests remaining in the current window. schema: type: string content: application/json: schema: $ref: '#/components/schemas/UsageEvent' example: id: usage_1a2b3c4d featureCode: api_calls value: 1 customerId: cus_1a2b3c4d eventId: request_123 ts: '2026-09-07T12:00:00.000Z' createdAt: '2026-09-07T12:00:00.000Z' properties: - property: endpoint value: /v1/search object: usage_event livemode: false '400': description: Bad request headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: validation_error code: validation_error message: The request contains an invalid parameter. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/validation_error.md '401': description: Unauthorized headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: authentication_error code: unauthorized message: A valid API key is required. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/unauthorized.md '402': description: Payment required headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: billing_error code: payment_failed message: The payment could not be completed. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/payment_failed.md '403': description: Forbidden headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: authentication_error code: forbidden message: You do not have permission to perform this operation. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/forbidden.md '404': description: Not found headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: not_found_error code: not_found message: The requested resource was not found. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/not_found.md '409': description: Conflict headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: conflict_error code: idempotency_in_progress message: >- A request with this idempotency key is still being processed. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/idempotency_in_progress.md '422': description: Unprocessable entity headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: validation_error code: validation_error message: >- The requested operation is not valid for the current configuration. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/validation_error.md '429': description: Too many requests headers: X-Request-Id: $ref: '#/components/headers/RequestId' RateLimit-Limit: description: Maximum number of requests allowed in the current window. schema: type: string RateLimit-Remaining: description: Requests remaining in the current window. schema: type: string RateLimit-Reset: description: Seconds until the rate limit window resets. schema: type: string Retry-After: description: Seconds to wait before retrying the request. schema: type: string content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: rate_limit_error code: rate_limited message: >- Too many requests. Retry after the interval specified in the Retry-After header. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/rate_limited.md '500': description: Internal server error headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: internal_error code: internal_error message: An unexpected error occurred while processing the request. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/internal_error.md '503': description: Service unavailable headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: internal_error code: idempotency_unavailable message: >- Idempotency storage is temporarily unavailable. Retry with the same idempotency key. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/idempotency_unavailable.md x-codeSamples: - lang: typescript label: TypeScript source: |- import { Commet } from "@commet/node"; const commet = new Commet({ apiKey: "ck_xxx" }); const usageEvent = await commet.usage.track({ featureCode: "api_calls", customerId: "user_123", model: "example", inputTokens: 1, outputTokens: 1, }); - lang: python label: Python source: |- from commet import Commet commet = Commet("ck_xxx") usage_event = commet.usage.track( feature_code="api_calls", customer_id="user_123", model="example", input_tokens=1, output_tokens=1, ) - lang: go label: Go source: "client, err := commet.New(\"ck_xxx\")\nif err != nil {\n\tlog.Fatal(err)\n}\nctx := context.Background()\n\nusageEvent, err := client.Usage.Track(ctx, &commet.TrackUsageParams{\n\tFeatureCode: \"api_calls\",\n\tCustomerID: \"user_123\",\n\tModel: func(value string) *string { return &value }(\"example\"),\n\tInputTokens: func(value int) *int { return &value }(1),\n\tOutputTokens: func(value int) *int { return &value }(1),\n})\nif err != nil {\n\tlog.Fatal(err)\n}" - lang: java label: Java source: |- import co.commet.Commet; import co.commet.params.TrackUsageParams; var commet = Commet.builder().apiKey("ck_xxx").build(); var usageEvent = commet.usage().track( TrackUsageParams.builder("api_calls", "user_123").model("example").inputTokens(1L).outputTokens(1L).build() ); - lang: php label: PHP source: |- use Commet\Commet; $commet = new Commet('ck_xxx'); $usageEvent = $commet->usage->track( featureCode: 'api_calls', customerId: 'user_123', model: 'example', inputTokens: 1, outputTokens: 1, ); components: headers: RequestId: description: >- Server-generated identifier that correlates this response with Platform logs. schema: type: string format: uuid schemas: UsageEvent: type: object properties: id: type: string featureCode: type: string value: type: number customerId: type: string eventId: anyOf: - type: string - type: 'null' ts: type: string format: date-time createdAt: type: string format: date-time properties: type: array items: type: object properties: property: type: string value: type: string required: - property - value additionalProperties: false consumption: type: object properties: model: type: string enum: - credits - balance deducted: type: number remaining: type: number blocked: type: boolean required: - model - deducted - remaining - blocked additionalProperties: false object: type: string const: usage_event livemode: type: boolean required: - id - featureCode - value - customerId - eventId - ts - createdAt - properties - object - livemode additionalProperties: false ErrorResponse: type: object properties: error: type: object properties: type: type: string code: type: string message: type: string param: type: string details: {} doc_url: type: string required: - type - code - message - doc_url additionalProperties: false required: - error additionalProperties: false securitySchemes: ApiKeyAuth: type: apiKey in: header name: x-api-key ```` ## Related topics - [Métricas y eventos de uso](/docs/es/dashboard-metrics-and-events.md) - [Manejo de errores](/docs/es/error-handling.md) - [Cobro por Tokens de IA](/docs/es/ai-token-billing.md) - [Addons](/docs/es/add-ons.md) - [usage.recorded](/docs/es/webhooks/usage-recorded.md) This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.