--- title: File Attachments product: vercel url: /docs/ai-gateway/sdks-and-apis/openai-chat-completions/images canonical_url: "https://vercel.com/docs/ai-gateway/sdks-and-apis/openai-chat-completions/images" last_updated: 2026-07-27 type: conceptual prerequisites: - /docs/ai-gateway/sdks-and-apis/openai-chat-completions - /docs/ai-gateway/sdks-and-apis related: - /docs/ai-gateway/sdks-and-apis/openai-chat-completions/chat-completions - /docs/ai-gateway/sdks-and-apis/openai-chat-completions/image-generation summary: Send images and PDF documents to a model using the OpenAI Chat Completions API. install_vercel_plugin: npx plugins add vercel/vercel-plugin --- # File Attachments Send images and PDFs alongside your text prompt by using an array of content parts in place of a plain string. Every part carries its own `type`, so one message can mix text, images, and documents. Model support varies. Check the [models list](/ai-gateway/models) for a model's input modalities before sending an attachment. ## Image attachments Send images as part of your chat completion request. Example request #### cURL ```bash filename="image-analysis.sh" IMAGE_B64=$(base64 -i image.png) curl -X POST "https://ai-gateway.vercel.sh/v1/chat/completions" \ -H "Authorization: Bearer $AI_GATEWAY_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "model": "anthropic/claude-opus-5", "messages": [ { "role": "user", "content": [ { "type": "text", "text": "What is in this image?" }, { "type": "image_url", "image_url": { "url": "data:image/png;base64,'"$IMAGE_B64"'" } } ] } ] }' ``` #### TypeScript ```typescript filename="image-analysis.ts" import fs from 'node:fs'; import OpenAI from 'openai'; const apiKey = process.env.AI_GATEWAY_API_KEY || process.env.VERCEL_OIDC_TOKEN; const openai = new OpenAI({ apiKey, baseURL: 'https://ai-gateway.vercel.sh/v1', }); // Read the image file as base64 const imageBuffer = fs.readFileSync('./image.png'); const imageBase64 = imageBuffer.toString('base64'); const completion = await openai.chat.completions.create({ model: 'anthropic/claude-opus-5', messages: [ { role: 'user', content: [ { type: 'text', text: 'Describe this image in detail.' }, { type: 'image_url', image_url: { url: `data:image/png;base64,${imageBase64}`, detail: 'auto', }, }, ], }, ], stream: false, }); console.log('Assistant:', completion.choices[0].message.content); console.log('Tokens used:', completion.usage); ``` #### Python ```python filename="image-analysis.py" import os import base64 from openai import OpenAI api_key = os.getenv('AI_GATEWAY_API_KEY') or os.getenv('VERCEL_OIDC_TOKEN') client = OpenAI( api_key=api_key, base_url='https://ai-gateway.vercel.sh/v1' ) # Read the image file as base64 with open('./image.png', 'rb') as image_file: image_base64 = base64.b64encode(image_file.read()).decode('utf-8') completion = client.chat.completions.create( model='anthropic/claude-opus-5', messages=[ { 'role': 'user', 'content': [ {'type': 'text', 'text': 'Describe this image in detail.'}, { 'type': 'image_url', 'image_url': { 'url': f'data:image/png;base64,{image_base64}', 'detail': 'auto' } } ] } ], stream=False, ) print('Assistant:', completion.choices[0].message.content) print('Tokens used:', completion.usage) ``` ## PDF attachments Send PDF documents as part of your chat completion request. Example request #### cURL ```bash filename="pdf-analysis.sh" PDF_B64=$(base64 -i document.pdf) curl -X POST "https://ai-gateway.vercel.sh/v1/chat/completions" \ -H "Authorization: Bearer $AI_GATEWAY_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "model": "anthropic/claude-opus-5", "messages": [ { "role": "user", "content": [ { "type": "text", "text": "Summarize this document." }, { "type": "file", "file": { "filename": "document.pdf", "file_data": "data:application/pdf;base64,'"$PDF_B64"'" } } ] } ] }' ``` #### TypeScript ```typescript filename="pdf-analysis.ts" import fs from 'node:fs'; import OpenAI from 'openai'; const apiKey = process.env.AI_GATEWAY_API_KEY || process.env.VERCEL_OIDC_TOKEN; const openai = new OpenAI({ apiKey, baseURL: 'https://ai-gateway.vercel.sh/v1', }); // Read the PDF file as base64 const pdfBuffer = fs.readFileSync('./document.pdf'); const pdfBase64 = pdfBuffer.toString('base64'); const completion = await openai.chat.completions.create({ model: 'anthropic/claude-opus-5', messages: [ { role: 'user', content: [ { type: 'text', text: 'What is the main topic of this document? Please summarize the key points.', }, { type: 'file', file: { data: pdfBase64, media_type: 'application/pdf', filename: 'document.pdf', }, }, ], }, ], stream: false, }); console.log('Assistant:', completion.choices[0].message.content); console.log('Tokens used:', completion.usage); ``` #### Python ```python filename="pdf-analysis.py" import os import base64 from openai import OpenAI api_key = os.getenv('AI_GATEWAY_API_KEY') or os.getenv('VERCEL_OIDC_TOKEN') client = OpenAI( api_key=api_key, base_url='https://ai-gateway.vercel.sh/v1' ) # Read the PDF file as base64 with open('./document.pdf', 'rb') as pdf_file: pdf_base64 = base64.b64encode(pdf_file.read()).decode('utf-8') completion = client.chat.completions.create( model='anthropic/claude-opus-5', messages=[ { 'role': 'user', 'content': [ { 'type': 'text', 'text': 'What is the main topic of this document? Please summarize the key points.' }, { 'type': 'file', 'file': { 'data': pdf_base64, 'media_type': 'application/pdf', 'filename': 'document.pdf' } } ] } ], stream=False, ) print('Assistant:', completion.choices[0].message.content) print('Tokens used:', completion.usage) ``` ## Next steps - [Chat completions](/docs/ai-gateway/sdks-and-apis/openai-chat-completions/chat-completions) - Request and response shapes for text - [Image generation](/docs/ai-gateway/sdks-and-apis/openai-chat-completions/image-generation) - Generate images rather than send them --- [View full sitemap](/docs/sitemap)