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

# Initiate invoice export (async)



## OpenAPI

````yaml /tango_projects/integrations/guides/invoice-outbound-api.yaml get /v1/projectmgmt/batch/invoices
openapi: 3.1.0
info:
  title: Tango Project Invoice Outbound API
  version: '1.1'
  description: |
    Async REST API for retrieving approved invoice records from Tango. Client
    initiates a GET against the invoices endpoint; Tango returns a `gu_id`
    immediately. Client then calls the Status endpoint with that `gu_id` to
    retrieve the full invoice payload (the same gu_id can be re-used multiple
    times to fetch the same batch). On successful export, Tango flags the
    invoices as `Exported`.

    Each invoice has a header plus an array of detail line items. Any field
    that is unconfigured or null in Tango is omitted from the JSON.
  x-direction: outbound
  x-source: Tango
  x-destination: Client System
servers:
  - url: https://api.tangoanalytics.com
    description: Production
  - url: https://testapi.tangoanalytics.com
    description: Test (SIT/UAT)
security:
  - xClientHeader: []
    xApiKeyHeader: []
tags:
  - name: Invoices
  - name: Status
paths:
  /v1/projectmgmt/batch/invoices:
    get:
      tags:
        - Invoices
      summary: Initiate invoice export (async)
      operationId: getInvoicesBatch
      parameters:
        - $ref: '#/components/parameters/XClient'
        - $ref: '#/components/parameters/XApiKey'
      responses:
        '200':
          description: |
            Async ack returning a gu_id. On error the gu_id is not generated.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/AcceptedResponse'
              examples:
                ok:
                  value:
                    status: OK
                    status_message: ''
                    gu_id: 721c54c4-c7aa-4fa1-8fdfd6-c0cee161694d
components:
  parameters:
    XClient:
      name: x-client
      in: header
      required: true
      schema:
        type: string
    XApiKey:
      name: x-api-key
      in: header
      required: true
      schema:
        type: string
  schemas:
    AcceptedResponse:
      type: object
      required:
        - status
      properties:
        status:
          type: string
          enum:
            - OK
            - Error
        status_message:
          type: string
        gu_id:
          type: string
          format: uuid
          description: Omitted on error.
  securitySchemes:
    xClientHeader:
      type: apiKey
      in: header
      name: x-client
    xApiKeyHeader:
      type: apiKey
      in: header
      name: x-api-key

````