Use DeepSeek Harness on mobile: DSH plugin remote access

There are two routes to DeepSeek Harness on mobile: browse the deployed Web UI from your phone's browser, or install a mobile DSH plugin for dedicated interface and connection adaptation (source). This guide covers how the two differ, how to set the bind address and auth, and how to handle connect failures, auth failures, and safe exposure.

How far mobile goes: DeepSeek Harness browser access vs a mobile DSH plugin

The core of the mobile story is "remote access", not "a mobile client": the DeepSeek Harness interface is already a Web UI, so a phone browser opens the same interface. Its Web UI is assembled on the browser side by front-end client modules (source), so accessing it from another device keeps roughly the same feature set. The two paths differ as follows:

1. Browser remote access — the phone browser connects to the dsh web service on your computer. Expected: nothing to install, features match the desktop, but the layout is a desktop design shrunk to a small screen.
2. A mobile plugin — install a DSH plugin optimized for small-screen interaction or connection style. Expected: smoother operation, possibly with notifications and direct LAN connection.

In one sentence: choose browser access to make it work, and look at a mobile plugin to make it pleasant.

Configure DeepSeek Harness mobile access: remote access and auth

Configuring mobile access comes down to two points: make the dsh web service reachable from the phone, and enable authentication. By default it listens only on localhost 127.0.0.1, so the phone cannot connect; but the official CLI does not support binding dsh web to 0.0.0.0 (--host 0.0.0.0 exits with a usage error), so the right move is an SSH tunnel or a reverse proxy plus auth, rather than opening the machine up. Steps:

1. Start the web service — run dsh web on your computer. Expected: http://127.0.0.1:3080 opens locally.
2. Confirm it works locally — verify the interface in the computer's browser first. Expected: you rule out problems with the service itself.
3. Choose a remote access method — the official CLI does not support binding 0.0.0.0, so share it through an SSH tunnel or a reverse proxy; the full steps are in How to deploy DeepSeek Harness to a remote server. Expected: the phone reaches the service through the tunnel or proxy, not by changing the bind address.
4. Configure authentication — set up auth as required when exposing beyond localhost; a prompt such as web authentication required means auth must be configured first. Expected: anonymous requests are refused.
5. Verify from the phone — connect the phone to the same network and open http://<computer-ip>:<port>. Expected: you can log in and see the Web UI.
6. (Optional) install a mobile plugin — pick one from the mobile / remote category on DSH Plugin Hub. Expected: small-screen experience or connection style improves.

DeepSeek Harness mobile connect and auth failures

When the phone cannot connect, check three layers in order: how the service is reached → network reachability → auth configuration, which saves the most time. The typical symptoms and handling for each layer:

1. The service is localhost-only — the service is bound to 127.0.0.1 only, so external devices can never connect. Expected: bring the service to the phone through an SSH tunnel or a reverse proxy (the official CLI does not support rebinding to 0.0.0.0).
2. Network unreachable — the phone and computer are not on the same subnet, or the system firewall blocks the port. Expected: confirm the same LAN and allow the port, then it connects.
3. Auth not passed — a web authentication required prompt or a rejected login. Expected: configuring credentials lets you in normally.
4. Wrong address entered — using localhost instead of the computer's actual IP. Expected: switching to the computer's LAN IP plus port works.

DSH plugin mobile access safety notes

1. Public exposure is high risk: it carries local file and command-execution ability, so prefer an intranet or a tunnel over the public internet.
2. Auth and encryption are mandatory: for public access, enforce authentication plus HTTPS and restrict source IPs.
3. Reclaim when done: after temporary remote access, drop the SSH tunnel or shut the reverse-proxy entry.
4. Vet plugin sources: mobile / remote plugins hold broad permissions, so check compatibility status and maintenance activity before installing.
5. Do not reuse weak passwords: keep the auth credential separate from other services to avoid a single leak taking everything down.
6. Local first, remote second: verify locally before opening remote access, so problems are easier to locate.

Sources: DeepSeek Harness docs - quickstart, docs - client modules subsystem, dsh-web-mobile (DSH Plugin Hub).