> ## Documentation Index > Fetch the complete documentation index at: https://docs.filexpress.app/llms.txt > Use this file to discover all available pages before exploring further. # Register movement > Cash income (`income`) or expense (`expense`) in an open cash register. Returns the updated summary. **Required permission:** `cash_register.operate` ## OpenAPI ````yaml /api-reference/openapi.en.json post /cash-registers/{id}/movements openapi: 3.0.3 info: title: FileXpress External API version: 1.0.0 description: >- API for integrating third-party systems with FileXpress: billing, HR, accounting, inventory, projects, accounts receivable and payable, treasury, pricing and promotions, and cash. Current base URL: /api/external/v1. The legacy unversioned path (/api/external) will be removed on January 1, 2027; migrate to /api/external/v1 (same endpoints, only the base URL changes). The v2 API (/api/external/v2) exposes currencies and exchange rates, sales and purchases in foreign currency, taxes by id, payrolls with branch, and errors with a stable `code`; its operations carry the /v2 prefix in the path. We suggest migrating to the available v2 routes before March 30, 2027. servers: - url: https://api.filexpress.app/api/external/v1 description: Production security: - ApiKey: [] tags: - name: General - name: Billing · Sales - name: Billing · Purchases - name: Billing · Customers - name: Billing · Suppliers - name: Billing · Products - name: Catalogs - name: HR · Employees - name: HR · Attendance - name: HR · Labor rules - name: HR · Schedules - name: HR · Holidays - name: HR · Attendance results - name: HR · Leave requests - name: HR · Payrolls - name: Accounting - name: Inventory - name: Projects - name: Accounts receivable - name: Accounts payable - name: Treasury - name: Pricing and promotions - name: Cash - name: Points of sale - name: API v2 · General - name: API v2 · Currencies and rates - name: API v2 · Countries - name: API v2 · Sales - name: API v2 · Purchases - name: API v2 · Payrolls paths: /cash-registers/{id}/movements: post: tags: - Cash summary: Register movement description: >- Cash income (`income`) or expense (`expense`) in an open cash register. Returns the updated summary. **Required permission:** `cash_register.operate` parameters: - name: id in: path required: true description: Cash register ID schema: type: string format: uuid example: 9d1c5a3e-4b7f-4e2a-9c1d-2f6b8a0e7c11 - $ref: '#/components/parameters/IdempotencyKey' requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/CashMovementRequest' example: type: expense amount: 20 description: Compra de hielo reference: REC-12 responses: '201': description: Movement registered content: application/json: schema: type: object required: - status - data properties: status: type: boolean example: true data: $ref: '#/components/schemas/CashMovementResult' example: status: true data: id: 3b8e2f10-7c4d-4a9e-b1f2-5d6c7e8f9a01 type: expense amount: 20 description: Compra de hielo reference: REC-12 summary: total_sales: 410 total_cash: 215 total_card: 180 total_other: 15 total_expenses: 20 more_income: 0 sales_count: 37 cash_movements: 1 expected_cash: 295 headers: Idempotent-Replayed: $ref: '#/components/headers/IdempotentReplayed' '401': $ref: '#/components/responses/E401' '403': $ref: '#/components/responses/E403' '404': description: Not found or belongs to another business content: application/json: schema: $ref: '#/components/schemas/Error' example: status: false message: Cash register not found '409': description: Cash register not open or idempotency conflict content: application/json: schema: $ref: '#/components/schemas/Error' examples: closed: summary: Caja cerrada value: status: false message: Cash register is not open. idem_body: summary: Idempotency-Key reutilizada con otro cuerpo value: status: false message: >- This Idempotency-Key was already used with a different request. idem_busy: summary: Petición con la misma llave en proceso value: status: false message: >- A request with this Idempotency-Key is already being processed. '422': description: Validation error content: application/json: schema: $ref: '#/components/schemas/Error' example: status: false message: Validation errors errors: amount: - The amount must be at least 0.01. '429': $ref: '#/components/responses/E429' components: parameters: IdempotencyKey: name: Idempotency-Key in: header required: false description: >- Optional. Unique key per operation (max. 100 characters, valid for 24 h per integration). A retry with the same key and the same body returns the original response (header `Idempotent-Replayed: true`) without repeating the operation; with a different body, or while the first is still in progress, it returns 409. schema: type: string maxLength: 100 example: pago-2026-10-06-000123 schemas: CashMovementRequest: type: object properties: type: type: string description: Type. enum: - income - expense amount: type: number minimum: 0.01 description: type: string maxLength: 255 reference: type: string maxLength: 100 required: - type - amount - description CashMovementResult: type: object properties: id: type: string format: uuid type: type: string description: Type. enum: - income - expense amount: type: number description: type: string reference: type: string nullable: true summary: $ref: '#/components/schemas/CashRegisterSummary' required: - id - type - amount - summary Error: type: object properties: status: type: boolean example: false message: type: string errors: type: object additionalProperties: type: array items: type: string description: Errors per field (validation only). required: - status - message CashRegisterSummary: type: object properties: total_sales: type: number total_cash: type: number total_card: type: number total_other: type: number total_expenses: type: number more_income: type: number sales_count: type: integer cash_movements: type: integer expected_cash: type: number description: Opening + cash sales − expenses + income. headers: IdempotentReplayed: description: >- `true` when the response is the replay of a previous request with the same Idempotency-Key. schema: type: string enum: - 'true' responses: E401: description: Missing or invalid API Key content: application/json: example: status: false message: Invalid API Key. E403: description: Integration without the required permission or deactivated content: application/json: example: status: false message: This integration does not have the 'hr.employees' permission. required_scope: hr.employees E429: description: Rate limit exceeded content: application/json: example: status: false message: Rate limit exceeded. Please try again later. rate_limit: 100 securitySchemes: ApiKey: type: apiKey in: header name: X-API-Key description: Integration API Key (Integrations → New Integration). ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.