> ## 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. # Generate an answer with a single document > **Deprecated — this endpoint will be removed in a future release. Use `POST /api/v3/ask` instead.** This endpoint can be used to ask a question about a document. The question is required and should be a string . The id of the document is a path parameter. ## OpenAPI ````yaml /api-reference/openapi-v2.yaml post /api/v2/files/{id}/ask-question openapi: 3.1.0 info: title: LightOn API version: 3.15.0 (v2) 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://api.lighton.ai security: [] tags: - name: Files Search description: Operations about files search - name: Models description: Operations about AI models - name: Files description: Operations about files - name: Workspaces description: Operations about workspaces - name: Upload Sessions description: Operations about upload sessions - name: Users description: Operations about users - name: Companies description: Operations about companies - name: SCIM description: Operations about SCIM - name: Feedbacks description: Operations about feedbacks - name: Reporting description: Operations about reporting - name: Platform Status description: Operations about platform status paths: /api/v2/files/{id}/ask-question: post: tags: - Files summary: Generate an answer with a single document description: >- **Deprecated — this endpoint will be removed in a future release. Use `POST /api/v3/ask` instead.** This endpoint can be used to ask a question about a document. The question is required and should be a string . The id of the document is a path parameter. operationId: api_v2_files_ask_question_create parameters: - in: path name: id schema: type: integer required: true requestBody: content: application/json: schema: $ref: '#/components/schemas/AskQuestionRequest' examples: ExampleQuestionString: value: question: example question summary: example question string application/x-www-form-urlencoded: schema: $ref: '#/components/schemas/AskQuestionRequest' multipart/form-data: schema: $ref: '#/components/schemas/AskQuestionRequest' required: true responses: '200': content: application/json: schema: $ref: '#/components/schemas/AskQuestionResponse' description: '' deprecated: true security: - bearerAuth: [] components: schemas: AskQuestionRequest: type: object description: Request serializer for asking a question about a document. properties: question: type: string description: The question to ask about the document maxLength: 2048 required: - question AskQuestionResponse: type: object description: >- Response serializer for the result of asking a question about a document. properties: response: type: string description: The generated response to the question chunks: type: array items: $ref: '#/components/schemas/DocumentChunkResponse' description: Relevant document chunks used to generate the response required: - chunks - response DocumentChunkResponse: type: object properties: id: type: integer readOnly: true uuid: type: string format: uuid readOnly: true content_id: type: - string - 'null' readOnly: true text: type: string readOnly: true metadata: allOf: - $ref: '#/components/schemas/ChunkMetadataResponse' readOnly: true description: >- Provenance and positioning metadata: page range, title, source filename, and neighbouring chunk UUIDs. document: type: - integer - 'null' readOnly: true document_attributes: type: - object - 'null' additionalProperties: {} readOnly: true chunk_type: allOf: - $ref: '#/components/schemas/ChunkTypeEnum' readOnly: true created_at: type: string format: date-time readOnly: true updated_at: type: string format: date-time readOnly: true required: - chunk_type - content_id - created_at - document - document_attributes - id - metadata - text - updated_at - uuid ChunkMetadataResponse: description: >- Provenance and positioning metadata returned alongside every retrieved chunk. properties: pages: default: '' description: >- 1-indexed page (or page range) of the parent document covered by the chunk. Single page: '5'. Multi-page span: '3-4'. title: Pages type: string total_pages: anyOf: - type: integer - type: 'null' default: null description: >- Total page count of the parent document. Null when unknown (e.g. spreadsheets). title: Total Pages title: default: '' description: Parent document's title. Empty when the document has no title. title: Title type: string source: default: '' description: Original filename of the parent document, e.g. 'design-doc.pdf'. title: Source type: string parser: default: '' description: Parser that produced the chunk (e.g. 'vision' for vision chunks). title: Parser type: string folder_name: default: '' description: >- Name of the immediate folder the document was imported from. Empty for direct uploads. title: Folder Name type: string coords: anyOf: - type: string - type: 'null' default: null description: >- Bounding boxes of the chunk's text on the source PDF, as a semicolon-joined string of 'page,x,y,w,h' tuples (e.g. '3,72.0,120.0,450.0,18.0;3,72.0,140.0,450.0,18.0'). Null when unavailable (spreadsheets, vision chunks). title: Coords previous: default: '' description: >- UUID of the previous chunk in the document. Empty for the first chunk. title: Previous type: string next: default: '' description: UUID of the next chunk in the document. Empty for the last chunk. title: Next type: string overlapping: default: '' description: >- Semicolon-joined UUIDs of chunks that share text with this chunk. Empty when there is no overlap. title: Overlapping type: string token_length: anyOf: - type: integer - type: 'null' default: null description: Number of tokens in the chunk text. Null for vision chunks. title: Token Length title: ChunkMetadataResponse type: object ChunkTypeEnum: enum: - text - table type: string description: |- * `text` - text * `table` - table securitySchemes: bearerAuth: type: http scheme: bearer description: >- Bearer authentication header of the form `Bearer `, where `` is your auth token. ````