> ## 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.

# Get a journal entry line

> Returns the full detail of a single journal entry line by ID. Each line belongs to a parent
journal entry and specifies the GL account, debit or credit amount, memo, and optional
dimension tags (department, class, project). Lines cannot be modified after the parent entry
is posted.
Requires `accounting:read` scope.




## OpenAPI

````yaml /openapi.yaml get /journal-entries/{id}/lines/{line_id}
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/{line_id}:
    get:
      tags:
        - Accounting
      summary: Get a journal entry line
      description: >
        Returns the full detail of a single journal entry line by ID. Each line
        belongs to a parent

        journal entry and specifies the GL account, debit or credit amount,
        memo, and optional

        dimension tags (department, class, project). Lines cannot be modified
        after the parent entry

        is posted.

        Requires `accounting:read` scope.
      operationId: getJournalEntryLineV1
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: string
            format: uuid
        - name: line_id
          in: path
          required: true
          schema:
            type: string
            format: uuid
      responses:
        '200':
          description: Single JE line
          content:
            application/json:
              schema:
                $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.

````