> ## Documentation Index
> Fetch the complete documentation index at: https://docs.finsync.ar/llms.txt
> Use this file to discover all available pages before exploring further.

# Create account on an existing client

> Adds an account to an existing client in the API-key company. Internal cajas (type=0) may have several accounts in the same currency. External clients (type=1) reuse the existing account when one already exists for that currency. Does not create currencies.



## OpenAPI

````yaml /docs/openapi.json post /api/accounts
openapi: 3.0.0
info:
  title: FinSync API Documentation
  version: 1.0.0
  description: API documentation for FinSync application
  contact:
    name: FinSync Support
    email: support@finsync.com
servers:
  - url: https://api.finsync.ar
    description: Direct Fly API (preferred for API keys and webhooks)
  - url: https://finsync.ar
    description: Same-origin via finsync.ar (Vercel rewrite)
security:
  - apiKey: []
tags:
  - name: Clients
    description: Operations related to clients and their accounts
  - name: Tags
    description: >-
      Company-scoped client labels (Configuración > Etiquetas). Distinct from
      the special Centro de resultados / Centro de costos tag used for budget
      clients.
  - name: Accounts
    description: Operations related to account balances
  - name: Cost Centers
    description: Company centros de resultados (cost_center_id) and their budgets
  - name: Operations
    description: Operations for creating and managing financial operations
  - name: Operation Types
    description: Company operation types management
  - name: Transaction Types
    description: Company transaction types management
  - name: WhatsApp Tools
    description: >-
      Company-scoped WhatsApp bot operation tools (Configuración > WhatsApp >
      Tools). Same WhatsAppOperationTool rows as the dashboard. Authenticate
      with x-api-key.
  - name: External client
    description: >-
      Exports for external (portal-linked) clients. Authenticate with
      `x-api-key` (company-owned client ID) or `Authorization: Bearer` (Auth.js
      session for an ExternalAccessGrant).
  - name: Mesas
    description: >-
      Company FX trading desks (mesas). Same records and paths as the dashboard
      Mesas module. Integrators authenticate with x-api-key; the dashboard uses
      an employee session. Superadmin must set mesas_enabled first; there is no
      public PATCH for that flag. created_by / opened_by / closed_by are null
      for API-key callers.
  - name: Home metrics
    description: >-
      Named dashboard home metrics (list + values). API keys receive the
      Métricas-group cards (day P&L, commissions, cost centers) without the
      metrics-password cookie. Employee sessions need the matching view
      permission; they still skip the UI password gate on this surface.
paths:
  /api/accounts:
    post:
      tags:
        - Accounts
      summary: Create account on an existing client
      description: >-
        Adds an account to an existing client in the API-key company. Internal
        cajas (type=0) may have several accounts in the same currency. External
        clients (type=1) reuse the existing account when one already exists for
        that currency. Does not create currencies.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - client_id
                - name
                - currency_name
              properties:
                client_id:
                  type: integer
                  description: Existing client ID (internal caja or external counterparty)
                name:
                  type: string
                  maxLength: 100
                  description: Account display name, e.g. Caja USD
                currency_name:
                  type: string
                  maxLength: 10
                  description: Currency code already used by the company, e.g. USD
      responses:
        '201':
          description: Account created (or the existing external account for that currency)
          content:
            application/json:
              schema:
                type: object
                properties:
                  id:
                    type: integer
                  client_id:
                    type: integer
                  name:
                    type: string
                  currency_name:
                    type: string
                  balance:
                    type: number
                  type:
                    type: string
                  created_at:
                    type: string
                    format: date-time
                  updated_at:
                    type: string
                    format: date-time
        '400':
          description: Bad request
        '401':
          description: Unauthorized - Missing or invalid API key
        '404':
          description: Client not found in this company
        '500':
          description: Server error
      security:
        - apiKey: []
components:
  securitySchemes:
    apiKey:
      type: apiKey
      in: header
      name: x-api-key
      description: API Key for authentication

````

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