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

# Create a custom GL account

> <Note>Required API key scope: `accounting:write`</Note>

Creates a non-system GL account for the entity. System accounts
(is_system_account=true or with a system_account_key) cannot be created
via the API -- they are provisioned by entity-seed-helpers.mjs only.

Account number is immutable post-create. account_type and normal_balance
are also immutable.




## OpenAPI

````yaml /openapi.yaml post /gl-accounts
openapi: 3.1.0
info:
  title: Arcus ERP Public API
  version: 1.0.0
  description: >
    Arcus ERP public REST API. Designed for external integrations and data
    migration.


    **Authentication.** Bearer token (API key) via the `Authorization` header.

    Format: `Authorization: Bearer ark_live_ent_<code>_<random>` (or
    `ark_test_*` for sandbox).

    API keys are issued per-entity in **Settings > Developers > API Keys**.


    **Entity scoping.** The entity is encoded in the API key prefix; routes are
    flat

    (e.g. `/v1/accounts`, `/v1/orders`, `/v1/products`). A small set of platform
    endpoints

    (migration, reconciliation, events, webhook endpoints, API keys) use the

    `/v1/entities/{entity_id}/...` form -- those are noted in their tags.


    **Key capabilities.**
      - Related-resource hydration via `?expand[]=` (see `x-arcus-expand` on each resource).
      - Cursor-based pagination (`starting_after` / `ending_before` / `limit`).
      - Idempotency via the `Idempotency-Key` header.
      - Webhook events for asynchronous notification.
      - Conditional requests / ETag for cache validation.
servers:
  - url: https://api.arcuserp.com/v1
    description: Arcus ERP API (accepts both live `ark_live_*` and test `ark_test_*` keys)
  - url: https://dev-api.arcuserp.com/v1
    description: >-
      Dev sandbox API (test-only data, accepts `ark_test_*` keys against dev
      RDS)
security: []
paths:
  /gl-accounts:
    post:
      tags:
        - Accounting
      summary: Create a custom GL account
      description: |
        <Note>Required API key scope: `accounting:write`</Note>

        Creates a non-system GL account for the entity. System accounts
        (is_system_account=true or with a system_account_key) cannot be created
        via the API -- they are provisioned by entity-seed-helpers.mjs only.

        Account number is immutable post-create. account_type and normal_balance
        are also immutable.
      operationId: createGlAccountV1
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - account_number
                - name
                - account_type
                - normal_balance
              properties:
                account_number:
                  type: string
                  description: Unique account number (e.g. '5500')
                name:
                  type: string
                description:
                  type: string
                account_type:
                  type: string
                  enum:
                    - asset
                    - liability
                    - equity
                    - revenue
                    - expense
                    - cogs
                account_sub_type:
                  type: string
                normal_balance:
                  type: string
                  enum:
                    - debit
                    - credit
                parent_account_id:
                  type: string
                  format: uuid
                  description: UUID of parent header account
                is_header:
                  type: boolean
                  description: True for rollup accounts that cannot receive postings
                tax_line_mapping:
                  type: string
                opening_balance:
                  type: number
                opening_balance_date:
                  type: string
                  format: date
      responses:
        '200':
          description: Created GL account
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/GlAccount'
        '400':
          $ref: '#/components/responses/Error'
        '401':
          $ref: '#/components/responses/Error'
        '403':
          $ref: '#/components/responses/Error'
      security:
        - ApiKeyAuth: []
components:
  schemas:
    GlAccount:
      type: object
      description: >
        A General Ledger account in the chart of accounts. Header accounts
        (is_header=true) aggregate child accounts and cannot receive postings
        (Rule A2 / Rule 21). Leaf accounts (is_header=false, is_active=true) are
        the only valid targets for journal entry lines. System accounts
        (is_system_account=true) are provisioned by entity-seed-helpers.mjs and
        cannot be created or modified via the API.
      properties:
        id:
          type: string
          format: uuid
          readOnly: true
        entity_id:
          type: string
          format: uuid
          readOnly: true
        account_number:
          type: string
          readOnly: true
          description: Immutable post-create (e.g. '1300')
        name:
          type: string
        description:
          type: string
          nullable: true
        account_type:
          type: string
          enum:
            - asset
            - liability
            - equity
            - revenue
            - expense
            - cogs
          readOnly: true
          description: Immutable post-create
        account_sub_type:
          type: string
          nullable: true
        normal_balance:
          type: string
          enum:
            - debit
            - credit
          readOnly: true
          description: Immutable post-create
        is_header:
          type: boolean
          description: >
            True for rollup accounts that aggregate children. Header accounts
            CANNOT receive journal entry line postings (Rule A2 /
            assertGLLinesPostable).
        parent_account_id:
          type: string
          format: uuid
          nullable: true
        is_system_account:
          type: boolean
          readOnly: true
          description: >
            True for accounts seeded by entity-seed-helpers.mjs. System accounts
            cannot be created, updated, or deleted via the API.
        system_account_key:
          type: string
          nullable: true
          readOnly: true
          description: >
            Lookup key used by posting helpers (e.g. ar_account, cogs, revenue,
            inventory_fg). Code uses getGLAccountByKey(entityId, key) instead of
            hardcoded account numbers.
        is_bank_account:
          type: boolean
          description: True for bank/cash accounts eligible for reconciliation
        is_active:
          type: boolean
        tax_line_mapping:
          type: string
          nullable: true
        opening_balance:
          type: number
          nullable: true
        opening_balance_date:
          type: string
          format: date
          nullable: true
        created_at:
          type: string
          format: date-time
          readOnly: true
        updated_at:
          type: string
          format: date-time
          readOnly: true
    ErrorEnvelope:
      type: object
      description: |
        Canonical error response envelope. All API errors use this shape.
      required:
        - error
        - code
      properties:
        error:
          type: string
          description: Machine-readable error key
          example: not_found
        code:
          type: string
          description: Machine-readable error code (often same as error)
          example: not_found
        type:
          type: string
          enum:
            - validation_error
            - permission_error
            - not_found
            - conflict
            - rate_limit
            - internal
            - expand_error
            - not_implemented
          example: not_found
        hint:
          type: string
          description: Human-readable one-sentence explanation (English)
          example: >-
            The requested order does not exist or does not belong to this
            entity.
        param:
          type: string
          description: The parameter that caused the error, if applicable
          example: expand[0]
        required:
          type: string
          description: The scope required (only on insufficient_scope errors)
          example: accounts:read
        request_id:
          type: string
          description: >-
            Unique request ID for support tracing (maps to CloudWatch log
            stream)
          example: req_abc123
  responses:
    Error:
      description: Error response (400/401/403/404/409/422/429/500)
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorEnvelope'
  securitySchemes:
    ApiKeyAuth:
      type: http
      scheme: bearer
      description: |
        API key issued per entity via Settings > Developers > API Keys.
        Each key carries scopes (e.g. orders:read, products:write).
        Bearer token format: Authorization: Bearer ark_live_ent_<code>_<random>
        Test keys use ark_test_ent_<code>_<random>. Both are issued per entity
        via Settings > Developers > API Keys.

````