Watching my agent work from the phone and the desktop at the same time

A developer built DeepSeek Phone Harness, an open-source tool that lets users monitor and control an AI agent from a phone. In a side-by-side test, the developer found that some experiences are actually better on mobile, such as approvals and questions appearing as cards in the message stream, and model switching via a thumb-reachable bottom sheet. The tool is MIT-licensed, requires zero npm dependencies, and can be set up in three minutes.

You'd expect the phone to be a "downgraded" web page. After a side-by-side test, I found some experiences are actually better on mobile. Before building DeepSeek Phone Harness, I set my own acceptance bar: the phone must reach 80% of the desktop web experience, or it's not done. After finishing, I ran a controlled test: the same task, watched simultaneously on a desktop browser and a phone browser. The result surprised me — a few experiences are genuinely better on mobile. Task: let the agent read the project config, summarize current progress, and run a test. | Dimension | Desktop web | Phone | |---|---|---| | Streaming output | Fine | Fine typewriter | | Tool-call visibility | Present | Stronger: each card shows the file path; tap for args + result | | Approvals | Dialog/panel | Cards inline in the message stream — no page switch | | Questions | Input takeover | Option cards, one tap | | Model switching | Dropdown | Bottom sheet, thumb-reachable | | Away from desk | Must be at the computer | Works from anywhere | On desktop, an approval is a separate dialog that interrupts what you're reading. On mobile, I made approvals and questions cards inserted directly into the message stream — the context of where the agent is and why it's asking stays continuous. "Read file → run command → edit code" — a vertical sequence of tool calls is made for a portrait screen . On desktop you juggle logs and lists; on mobile it's one clean timeline: 📄 read C:/.../config.json ● done ⚙️ pwsh npm test ● running… Model switching, attachments, card expansion — everything lives within thumb reach. Mobile is not a replacement for the desktop — heavy work editing lots of code, digging logs, multi-terminal still belongs at a desk. But mobile closes the desktop's biggest gap: the moments you're not at the computer. "Wherever you are, your agent is too" — that's mobile's real value, not "a smaller webpage." Open source MIT : Direct 4G/5G free Tailscale , three-minute setup, zero npm dependencies. Which of your agent tasks could be done while you're away from the desk? List them below — I'll see what belongs on the roadmap.