How to use box by Simular with DeepSeek Harness

Give DeepSeek a computer of its own in the cloud. The box by Simular plugin for DeepSeek Harness (dsh) gives DeepSeek a cloud desktop with Chrome and a shell. It can open websites, click, type, read the screen and run commands there.

Read the Quick Start

What DeepSeek can do with box

• Browse for you. "Open Google, find the cheapest flights to Tokyo next week and summarise them."
• Bulk work at a low model cost. Let DeepSeek handle long, repetitive tasks on the box, such as copying data from many pages into a sheet.
• Take over when another agent stops. If Claude hits its usage limit, DeepSeek can continue on the same box, with the same tabs and files.

Set up box in DeepSeek Harness

dsh can't sign in through a browser, so it uses a personal key from your Access page. Follow DeepSeek Harness in the MCP guide to install the plugin and set the key.

Keep the key out of chats and shared files. You can revoke it on your Access page.

Try these prompts

• "Use box to open Google, find the cheapest flights to Tokyo next week and summarise them."
• "Use box to open GitHub Trending and tell me what today's top 3 repositories do."
• "Use box to visit these 10 product pages and put name and price in a CSV."

What box adds to DeepSeek

box gives DeepSeek a separate cloud desktop: Chrome, files and a shell that stay signed in, that your other agents share, and that you can watch and take over.

FAQ

• Why a key instead of a sign-in? dsh can't open the browser sign-in flow, so it sends a personal key as a header.
• Does it use my DeepSeek account? DeepSeek uses its own model. Model calls made by box's own tools use box credits.
• Can I use the same box with Claude or ChatGPT? Yes. All your agents share one box.
• How do I remove access? Revoke the key on your Access page.

Troubleshooting

No box tools? See DeepSeek Harness in the MCP guide and Troubleshooting.

Related: Quick Start · Connect box over MCP