> ## 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.

# List lines for a journal entry

> Returns the individual debit/credit lines for a journal entry, with optional
dimension expansion (department, class, project).




## OpenAPI

````yaml /openapi.yaml get /journal-entries/{id}/lines
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:
  /journal-entries/{id}/lines:
    get:
      tags:
        - Accounting
      summary: List lines for a journal entry
      description: >
        Returns the individual debit/credit lines for a journal entry, with
        optional

        dimension expansion (department, class, project).
      operationId: listJournalEntryLinesV1
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: string
            format: uuid
        - name: expand[]
          in: query
          schema:
            type: string
          description: Expand gl_account or dimensions on each line.
      responses:
        '200':
          description: Journal entry lines
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    type: array
                    items:
                      $ref: '#/components/schemas/JournalEntryLine'
        '401':
          $ref: '#/components/responses/Error'
        '403':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
      security:
        - ApiKeyAuth: []
components:
  schemas:
    JournalEntryLine:
      type: object
      description: >
        A single debit or credit line within a journal entry. Exactly one of
        debit_amount or credit_amount is > 0. account_id must reference a
        postable leaf account (Rule A2). Verified against live dev RDS
        accounting.journal_entry_lines.
      properties:
        id:
          type: string
          format: uuid
          readOnly: true
        journal_entry_id:
          type: string
          format: uuid
          readOnly: true
        line_number:
          type: integer
          readOnly: true
        account_id:
          type: string
          format: uuid
        debit_amount:
          type: number
          minimum: 0
          description: Debit amount (0 if credit line)
        credit_amount:
          type: number
          minimum: 0
          description: Credit amount (0 if debit line)
        description:
          type: string
          nullable: true
        location_id:
          type: string
          format: uuid
          nullable: true
        department_id:
          type: string
          format: uuid
          nullable: true
        class_id:
          type: string
          format: uuid
          nullable: true
        project_id:
          type: string
          format: uuid
          nullable: true
        reconciled:
          type: boolean
          readOnly: true
        reconciled_at:
          type: string
          format: date-time
          nullable: true
          readOnly: true
        created_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.

````