> ## Documentation Index > Fetch the complete documentation index at: https://docs.lighton.ai/llms.txt > Use this file to discover all available pages before exploring further. # Render a document as PDF > Convert a document into a PDF suitable for inline preview. Accepts a **file upload** (multipart/form-data), a **document URL**, or a **file_id** referencing a document already ingested in the platform (JSON body). The conversion is synchronous — the PDF bytes are returned directly. **Supported file types:** `.pdf`, `.png`, `.jpg`, `.jpeg`, `.pptx`, `.ppt`, `.odp`, `.docx`, `.odt`, `.doc`, `.html`, `.xhtml` **Size limit:** 20 MB. ## OpenAPI ````yaml /api-reference/openapi-v3.yaml post /api/v3/preview openapi: 3.1.0 info: title: LightOn API version: 3.15.0 (v3) description: >- LightOn gives you an API to search, parse, and ingest documents at scale. Build knowledge-retrieval pipelines without managing vector databases or OCR models. servers: - url: https://paradigm.lighton.ai security: [] tags: - name: Agents description: Operations about agents - name: Threads description: Operations about agents conversation threads - name: Tools description: Operations about native tools - name: Models description: Operations about AI models - name: MCP description: Operations about MCP servers - name: Sources description: Operations about sources used by agents conversation threads - name: Artifacts description: Operations about artifacts generated by agents conversation threads - name: Agent description: >- Operations about agents (deprecated). Please use the 'Agents' API component instead. - name: Files description: Operations about files - name: Facets description: Operations about facets - name: Tags description: Operations about tags - name: Workspaces description: Operations about workspaces - name: Files Processing description: Operations about files processing - name: Users description: Operations about users - name: API Keys description: Operations about API keys - name: User Groups description: Operations about user groups - name: SCIM description: Operations about SCIM paths: /api/v3/preview: post: tags: - Models summary: Render a document as PDF description: >- Convert a document into a PDF suitable for inline preview. Accepts a **file upload** (multipart/form-data), a **document URL**, or a **file_id** referencing a document already ingested in the platform (JSON body). The conversion is synchronous — the PDF bytes are returned directly. **Supported file types:** `.pdf`, `.png`, `.jpg`, `.jpeg`, `.pptx`, `.ppt`, `.odp`, `.docx`, `.odt`, `.doc`, `.html`, `.xhtml` **Size limit:** 20 MB. operationId: api_v3_preview_create requestBody: content: multipart/form-data: schema: multipart/form-data: type: object properties: file: type: string format: binary description: The document to convert. application/json: type: object properties: document: type: string format: uri description: Publicly accessible URL of the document to convert. file_id: type: integer description: >- ID of a document already ingested in the platform. Mutually exclusive with `document`. examples: RenderAPDFViaFileUpload: value: file: (binary) summary: Render a PDF via file upload description: Upload a document file directly for synchronous PDF rendering. application/x-www-form-urlencoded: schema: multipart/form-data: type: object properties: file: type: string format: binary description: The document to convert. application/json: type: object properties: document: type: string format: uri description: Publicly accessible URL of the document to convert. file_id: type: integer description: >- ID of a document already ingested in the platform. Mutually exclusive with `document`. application/json: schema: multipart/form-data: type: object properties: file: type: string format: binary description: The document to convert. application/json: type: object properties: document: type: string format: uri description: Publicly accessible URL of the document to convert. file_id: type: integer description: >- ID of a document already ingested in the platform. Mutually exclusive with `document`. examples: RenderADocumentViaURL: value: document: https://example.com/report.docx summary: Render a document via URL description: Provide a publicly accessible document URL. RenderAnIngestedDocumentByID: value: file_id: 42 summary: Render an ingested document by ID description: Reference a document already ingested in the platform. responses: '200': description: PDF rendered successfully. Response body is the raw PDF bytes. '400': content: application/json: schema: $ref: '#/components/schemas/APIV3ErrorResponse' examples: UnsupportedFormat: value: id: null code: 400 error: unsupported_format detail: Unsupported document format. doc_url: https://developers.lighton.ai/errors#unsupported_format summary: Unsupported format description: Bad request — missing document, unsupported format, or invalid URL. '401': content: application/json: schema: $ref: '#/components/schemas/APIV3ErrorResponse' examples: Unauthorized: value: id: null code: 401 error: unauthorized detail: >- Authentication credentials were not provided or are invalid. doc_url: https://developers.lighton.ai/errors#unauthorized description: Authentication credentials were not provided or are invalid '413': content: application/json: schema: $ref: '#/components/schemas/APIV3ErrorResponse' examples: PayloadTooLarge: value: id: null code: 413 error: payload_too_large detail: File exceeds the 20 MB size limit. doc_url: https://developers.lighton.ai/errors#payload_too_large summary: Payload too large description: File exceeds the 20 MB size limit. '422': content: application/json: schema: $ref: '#/components/schemas/APIV3ErrorResponse' examples: ConversionFailed: value: id: null code: 422 error: validation_error detail: Conversion failed — corrupt file or LibreOffice error. doc_url: https://developers.lighton.ai/errors#validation_error summary: Conversion failed description: Conversion failed — corrupt file or LibreOffice error. '429': content: application/json: schema: $ref: '#/components/schemas/APIV3ErrorResponse' examples: TooManyRequests: value: id: null code: 429 error: too_many_requests detail: Too many requests. Please try again later. doc_url: https://developers.lighton.ai/errors#too_many_requests summary: Too Many Requests description: Too many requests '503': description: >- API is under maintenance. Check `GET /api/v3/system/status` for active periods and retry. content: application/json: schema: $ref: '#/components/schemas/ServiceMaintenance503' security: - bearerAuth: [] components: schemas: APIV3ErrorResponse: type: object properties: id: type: - string - 'null' description: >- Job/resource id when one already exists (useful for async error diagnosis); null otherwise. code: type: integer description: HTTP status code error: type: string description: Error code used by the UI as a translation key detail: type: string description: Human-readable error message for developers doc_url: type: string description: Link to the error-code documentation page required: - code - detail - doc_url - error - id ServiceMaintenance503: type: object description: >- Returned by the maintenance middleware when the requested endpoint is blocked. required: - detail - error - mode properties: detail: type: string example: System is under maintenance. error: type: string example: service_maintenance mode: type: string enum: - full_shutdown - warning_banner description: >- `full_shutdown` blocks all traffic; `warning_banner` also blocks and shows a dismissible toast. reason: type: string description: Operator-supplied maintenance reason, if any. started_at: type: string format: date-time endpoint_category_names: type: array items: type: string description: >- Non-empty only for category-scoped periods. Empty means all endpoints are affected. securitySchemes: bearerAuth: type: http scheme: bearer description: >- Bearer authentication header of the form `Bearer `, where `` is your auth token. ````