--- title: "DeepSeek API, Web Search \u0026 Vision in Visual Studio 2026 | iolys" description: "Use DeepSeek in Visual Studio 2026 with your API key. Search the web with native Web Search, check your balance, and attach images with a Vision model." url: "https://getiolys.com/providers/deepseek" language: "en" updated: "2026-09-19" --- # Use DeepSeek for C# and .NET in Visual Studio 2026. Bring DeepSeek models into a C# and .NET workflow built around Visual Studio 2026. iolys connects through the provider API while keeping the active solution, model, tool activity, and permissions clear. - Provider: DeepSeek - Connection type: Provider API - Access: Keep the provider relationship direct - Who pays for the AI usage: Uses your own API key, billed by the provider as prepaid credits or pay-as-you-go. There is no subscription to reuse. - Where the model runs: The model runs in the provider's own cloud service. - Best for: C# generation, debugging, code explanation, refactoring, and cost-conscious model selection for .NET work. - Official site: https://www.deepseek.com/en/ Use your own DeepSeek credentials and provider billing. iolys adds the Visual Studio 2026 workflow without reselling tokens or forcing a bundled model plan. ## How to connect DeepSeek in Visual Studio 2026 1. Open Manage Providers, choose Add Provider, and select DeepSeek. 2. Paste your DeepSeek API key and use Test Connection to load the available models. 3. Choose your model in the chat. Select a model marked Vision when attaching images. ## What you get - **Connect with one key** — Add your DeepSeek API key in Manage Providers and test the connection to discover compatible models. - **Keep your balance in view** — Open Show usage to see the available API balance reported by DeepSeek. - **Search with DeepSeek** — Enable Web Search in the selected model’s Tools section to use DeepSeek’s native web_search tool. - **Bring images into the task** — Choose a Vision model and attach an image alongside your prompt for visual context. ## Requirements iolys targets the Visual Studio 2026 IDE on 64-bit Windows. It requires access to a supported AI provider or a local Ollama instance. Git is required for isolated parallel workspaces. Visual Studio Code is a separate editor; iolys is an extension for the Visual Studio IDE. ## Price All currently available iolys features are free for personal and commercial use. AI provider subscriptions, API usage, and infrastructure costs remain separate. iolys does not include a bundled model allowance. ## DeepSeek questions ### How can I use DeepSeek in Visual Studio for C#? Install the iolys extension for Visual Studio 2026 and open your C# solution. Open Manage Providers, choose Add Provider, and select DeepSeek. Paste your DeepSeek API key and use Test Connection to load the available models. Choose your model in the chat. Select a model marked Vision when attaching images. You can then ask DeepSeek to help with your C# and .NET code from the iolys workspace. ### Is there a VSIX extension to use DeepSeek in Visual Studio? Yes. iolys is a VSIX extension for Visual Studio 2026, and DeepSeek is one of the provider connections it ships with. Install the iolys VSIX once from the Visual Studio Marketplace, then add DeepSeek from the Manage Providers panel; there is no separate VSIX per provider. ### Can I use DeepSeek in Visual Studio 2026? Yes, with the iolys extension. It provides a DeepSeek provider connection for Visual Studio 2026, authenticated with your own API key. ### How do I connect DeepSeek with my API key? Open Manage Providers, add DeepSeek, paste your API key, and select Test Connection. iolys supplies the DeepSeek endpoint and enables compatible models automatically. Your own DeepSeek API account and billing are used. ### Can I see my DeepSeek usage in Visual Studio? Yes. Open Show usage from the iolys chat toolbar. DeepSeek Usage displays the available API balance and currency reported by your account, rather than a subscription usage percentage. ### Does iolys support DeepSeek’s native web_search tool? Yes. Select a compatible DeepSeek model, open the Tools tab, and enable Web Search in the Model section. This makes DeepSeek’s native web_search tool available to search the web and read pages in your conversation. The screenshot shows it enabled for deepseek-v4-flash; availability depends on the selected model. ### Can DeepSeek work with images in iolys? Yes, when you select a compatible model marked Vision. Attach an image through Add context and Add file, then write your question. The model shown on this page is deepseek-v4-flash-vision-exp, an experimental model. Available models depend on your provider connection. ### Do all DeepSeek models accept images? No. Select a model marked Vision before attaching images. Text-only models do not gain image support simply by adding a file. ### Can I use DeepSeek alongside Codex or Gemini? Yes. iolys is designed for multiple providers in the same Visual Studio 2026 workflow. ## Related pages - [Bring Your Own AI Subscription to Visual Studio 2026 | iolys](https://getiolys.com/) - [Bring Your Own Model (BYOM) in Visual Studio 2026 | iolys](https://getiolys.com/byom) - [AI coding agent capabilities for Visual Studio | iolys](https://getiolys.com/capabilities) - [Visual Studio integrations for C# and .NET | iolys](https://getiolys.com/integrations) - [GitHub Copilot alternative for Visual Studio and C# | iolys](https://getiolys.com/copilot-alternative-visual-studio) - [AI providers and BYOS for Visual Studio 2026 | iolys](https://getiolys.com/providers) - [What is iolys? AI coding agent harness for Visual Studio | iolys](https://getiolys.com/what-is-iolys) - [The story behind iolys | From iolite to AI in Visual Studio](https://getiolys.com/our-story) - [Install iolys from the Visual Studio Marketplace](https://marketplace.visualstudio.com/items?itemName=iolys.iolys-visual-studio) - [iolys blog](https://getiolys.com/blog)