> ## Documentation Index > Fetch the complete documentation index at: https://docs.cula.tech/llms.txt > Use this file to discover all available pages before exploring further. # Upload a file > Uploads a file as `multipart/form-data` and attaches it to a site. The binary must be sent in the `file` field and may not exceed 100 MB. ## OpenAPI ````yaml /openapi.json post /files openapi: 3.1.0 info: title: Cula Tracking API version: 0.3.10 servers: - url: https://api.demo.cula.earth/tracking/v1 security: [] tags: - name: Organisations description: '' - name: Sites description: '' - name: Machines description: '' - name: Machine Variables description: '' - name: Machine Data Imports description: '' - name: Delivery Configs description: '' - name: Deliveries description: '' - name: Material Sourcing Configs description: '' - name: Material Sourcings description: '' - name: Material Conversion Configs description: '' - name: Material Conversions description: '' - name: Material Utilization Configs description: '' - name: Material Utilizations description: '' - name: Material Batches description: '' - name: Material Pools description: '' - name: Material Containers description: '' - name: Sinks description: '' - name: Documents description: '' - name: Webhooks description: '' paths: /files: post: tags: - Files summary: Upload a file description: >- Uploads a file as `multipart/form-data` and attaches it to a site. The binary must be sent in the `file` field and may not exceed 100 MB. parameters: - name: Cula-Organisation-Id in: header description: >- ID of the organisation the request operates on behalf of (e.g. `org_...`). Must be an organisation the API client has access to. required: true schema: type: string example: org_01k83mfmhgchya944v86ryvhpq requestBody: required: true content: multipart/form-data: schema: $ref: '#/components/schemas/CreateFileRequest' responses: '201': description: The metadata of the newly uploaded file. content: application/json: schema: $ref: '#/components/schemas/GetFileResponse' '400': description: Invalid request payload or parameters. content: application/json: schema: $ref: '#/components/schemas/Error' example: code: bad_request message: The field limit must not be greater than 100. '401': description: Missing or invalid access token. content: application/json: schema: $ref: '#/components/schemas/Error' example: code: unauthorized message: Invalid or expired token '409': description: Conflicting resource state. content: application/json: schema: $ref: '#/components/schemas/Error' example: code: conflict message: >- There exists already an object with external ID MY-CUSTOM-ID within this organisation. '415': description: Unsupported file type. content: application/json: schema: $ref: '#/components/schemas/Error' example: code: unsupported_media_type message: The file type is not supported. '500': description: Unexpected server error. content: application/json: schema: $ref: '#/components/schemas/Error' example: code: internal_server_error message: Internal server error. security: - AccessToken: [] components: schemas: CreateFileRequest: type: object properties: file: type: string format: binary description: The file to be uploaded. site_id: type: string example: ste_01k8g7aec6dt5zrtamc72ww446 description: >- The ID of the site the file will belong to. Provide exactly one of `site_id` or `site_external_id`. site_external_id: type: string example: SITE-EXT-0001 description: >- The external ID you assigned to the site the file will belong to. Provide exactly one of `site_id` or `site_external_id`. nullable: false maxLength: 100 minLength: 1 pattern: ^[A-Za-z0-9\-_]+$ external_id: type: string example: MY-CUSTOM-ID description: >- A optional custom ID that can be set to an internal ID from your system. This ID must be unique within all objects of the organisation you operate in. You can later use this external ID to reference and query this object. Be aware that you can update this ID later. If you need an immutable ID, use the object ID returned when creating the object. nullable: false maxLength: 100 minLength: 1 pattern: ^[A-Za-z0-9\-_]+$ required: - file GetFileResponse: type: object properties: id: type: string example: fle_01kw9grq4tecva35wdpstzcj5z description: ID of the file. external_id: type: string nullable: true example: MY-CUSTOM-ID description: Optionally assigned external ID of the file. site: description: The site that owns this file. allOf: - $ref: '#/components/schemas/SiteReference' name: type: string example: sink_confirmation.pdf description: The original filename of the uploaded binary. type: type: string example: application/pdf description: >- The MIME type of the file, detected from its contents at upload time. size: type: integer example: 482117 description: The size of the file in bytes. created_at: type: string format: date-time example: '2025-10-10T21:03:58Z' description: The ISO 8601 timestamp at which the file was uploaded. required: - id - external_id - site - name - type - size - created_at Error: type: object properties: code: type: string example: bad_request message: type: string example: The field limit must not be greater than 100. required: - code - message SiteReference: type: object properties: id: type: string nullable: true example: ste_01k8g7aec6dt5zrtamc72ww446 external_id: type: string nullable: true example: SITE-EXT-0001 description: >- References a site by its ID and the external ID you assigned to it (if any). required: - id - external_id securitySchemes: AccessToken: type: oauth2 flows: clientCredentials: tokenUrl: https://auth.demo.cula.earth/oauth2/token scopes: {} description: >- OAuth 2.0 client credentials. Exchange your client_id and client_secret for an access token scoped to the organisation that provides data access. ````