> ## Documentation Index > Fetch the complete documentation index at: https://docs.metronome.com/llms.txt > Use this file to discover all available pages before exploring further. # Set a contract usage filter > If a customer has multiple contracts with overlapping rates, the usage filter routes usage to the appropriate contract based on a predefined group key. As an example, imagine you have a customer associated with two projects. Each project is associated with its own contract. You can create a usage filter with group key `project_id` on each contract, and route usage for `project_1` to the first contract and `project_2` to the second contract. ### Use this endpoint to: - Support enterprise contracting scenarios where multiple contracts are associated to the same customer with the same rates. - Update the usage filter associated with the contract over time. ### Usage guidelines: To use usage filters, the `group_key` must be defined on the billable metrics underlying the rate card on the contracts. ## OpenAPI ````yaml /openapi.json post /v1/contracts/setUsageFilter openapi: 3.0.1 info: title: Metronome version: 1.0.0 servers: - url: https://api.metronome.com description: Production server security: - bearerAuth: [] tags: - name: Customers description: >- [Customers](https://docs.metronome.com/provisioning/create-customers/) in Metronome represent your users for all billing and reporting. Use these endpoints to create, retrieve, update, and archive customers and their billing configuration. - name: Billable metrics description: >- [Billable metrics](https://docs.metronome.com/understanding-metronome/how-metronome-works#billable-metrics) in Metronome represent the various consumption components that Metronome meters and aggregates. - name: Usage description: >- [Usage events](https://docs.metronome.com/connecting-metronome/send-usage-data/) are the basis for billable metrics. Use these endpoints to send usage events to Metronome and retrieve aggregated event data. - name: Products description: Products are the items that customers purchase. - name: Rate cards description: Rate cards are used to define default pricing for products. - name: Contracts description: >- A contract defines a customer’s products, pricing, discounts, commitments, and more. Use these endpoints to create and update contracts data. - name: Credits and commits description: Credits and commits are used to manage customer balances. - name: Invoices description: >- [Invoices](https://docs.metronome.com/invoicing/) reflect how much a customer spent during a period, which is the basis for billing. Metronome automatically generates invoices based upon your pricing, packaging, and usage events. Use these endpoints to retrieve invoices. - name: Alerts description: >- [Alerts](https://docs.metronome.com/connecting-metronome/alerts/) monitor customer spending, balances, and other billing factors. Use these endpoints to create, retrieve, and archive customer alerts. To view sample alert payloads by alert type, navigate [here.](https://docs.metronome.com/manage-product-access/create-manage-alerts/#webhook-notifications) - name: Custom fields description: >- [Custom fields](https://docs.metronome.com/integrations/custom-fields/) enable adding additional data to Metronome entities. Use these endpoints to create, retrieve, update, and delete custom fields. - name: Security description: >- [Security](https://docs.metronome.com/developer-resources/security/) endpoints allow you to retrieve security-related data. - name: Settings description: >- Use these endpoints to configure a billing API key, a webhook secret, or invoice finalization behavior. - name: Named schedules description: >- Named schedules are used for storing custom data that can change over time. Named schedules are often used in custom pricing logic. paths: /v1/contracts/setUsageFilter: post: tags: - Contracts summary: Set a contract usage filter description: > If a customer has multiple contracts with overlapping rates, the usage filter routes usage to the appropriate contract based on a predefined group key. As an example, imagine you have a customer associated with two projects. Each project is associated with its own contract. You can create a usage filter with group key `project_id` on each contract, and route usage for `project_1` to the first contract and `project_2` to the second contract. ### Use this endpoint to: - Support enterprise contracting scenarios where multiple contracts are associated to the same customer with the same rates. - Update the usage filter associated with the contract over time. ### Usage guidelines: To use usage filters, the `group_key` must be defined on the billable metrics underlying the rate card on the contracts. operationId: setUsageFilter-v1 requestBody: description: Set usage filter for contract content: application/json: schema: $ref: '#/components/schemas/SetUsageFilterPayload' example: customer_id: 13117714-3f05-48e5-a6e9-a66093f13b4d contract_id: d7abd0cd-4ae9-4db7-8676-e986a4ebd8dc group_key: business_subscription_id group_values: - ID-1 - ID-2 starting_at: '2020-01-01T00:00:00.000Z' responses: '200': description: Success '400': description: Bad request content: application/json: schema: $ref: '#/components/schemas/Error' '404': $ref: '#/components/responses/NotFound' components: schemas: SetUsageFilterPayload: type: object required: - customer_id - contract_id - group_key - group_values - starting_at properties: customer_id: type: string format: uuid contract_id: type: string format: uuid group_key: type: string group_values: type: array items: type: string starting_at: type: string format: date-time Error: required: - message type: object properties: message: type: string responses: NotFound: description: The specified resource was not found content: application/json: schema: $ref: '#/components/schemas/Error' securitySchemes: bearerAuth: type: http scheme: bearer ````