Every harness put the agent on your phone
An agent run is long and the point is not to babysit it. That only works if you find out the moment a run finishes or gets blocked, wherever you are. Three harnesses answered that in 2026, at three different depths.
Cursor: full mobile client
Cursor 3.9 (June 2026) shipped an iOS app. It launches cloud agents with voice input and slash commands, and its remote control feature directs your desktop agents from the phone. Live Activities and push notifications track agent status on the lock screen. This is the most complete "run it from your pocket" story of the three. See the Cursor CLI sheet.
Claude Code: notifications first
Claude Code on the web added mobile push notifications in Week 16 (April 2026). Your phone pings when a long task finishes or when Claude needs you. The bet is lighter: get told the instant you are needed, then move to a real screen to act. It pairs with background sessions and routines. See the Claude Code sheet.
Codex: pairing and grants
Codex 0.137 (June 2026) added remote control, where a client initiates pairing and manages controller grants. This is the plumbing for driving a session from another device, with explicit control over who is allowed to drive. See the Codex CLI sheet.
Which to expect what from
| Harness | Depth | What it gives you |
|---|---|---|
| Cursor | Full client | Launch, voice, remote-control desktop from iOS |
| Claude Code | Notifications | A ping when a task finishes or needs you |
| Codex | Pairing layer | Client-initiated pairing and controller grants |
These are not equivalent — match the tool to how much you want to do from a phone versus how much you just want to know.