I run a one-person studio, and DeepSeek Harness (DSH) is where I spend my working day: chats with agents that write code, run shell commands and produce documents on my own server. DSH has a plugin system, and over the last two months I wrote the pieces I kept missing. Now they are public on GitHub and npm: twelve plugins and one companion service, MIT licensed (one is Apache-2.0).
A disclosure before anything else: these were written with AI coding agents, mostly running inside DSH itself, under my direction. I decided what to build, reviewed the designs and the diffs, ran the tests and I use every one of them daily. Versions go from 0.1 to 2.1, so please treat them as beta and tell me what breaks.
Agents produce files: reports, dashboards, small web apps. dsh-artifacts adds an Artifacts tab to the right sidebar that lists every file an agent wrote and previews it in place, with live reload, version history, a diff view and a public link toggle. Markdown is rendered on the server into themed pages with KPI tiles, charts, timelines and diagrams, so an agent writes a few KB of Markdown instead of a whole HTML page. Agents also get a template library: a dashboard becomes one JSON file passed to artifact_from_template.
IMAP, POP3 and SMTP accounts, Gmail and Microsoft 365 through OAuth2 with your own client, a Mail tab for reading, and mail_* tools for agents. The part I care about most is the safety rule: by default agents only create drafts, and every send result starts with SENT, DRAFT ONLY or SCHEDULED, so neither the model nor I can misread what happened. Remote images go through a signed server proxy instead of the browser.
A Phone tab with SMS threads, calls and a keypad. Call audio goes through your own server over one encrypted socket, so it works on networks that block WebRTC. Live, Voicemail and Do not disturb modes come with live voicemail transcripts and a Pick up button. It works with Twilio numbers and with SIP lines bridged through Asterisk, and it can host a Telegram account. Agents get phone_* and telegram_* tools with rate limits and a kill switch.
Some networks inspect TLS. dsh-seal is a small Go reverse proxy plus a service worker that it injects into the DSH page: after the first page load every request, event stream and WebSocket message travels inside a sealed channel (ECDH P-256 per page load, AES-256-GCM per stream direction, a pinned server identity). The middle box sees the host name and the traffic volume, not paths, queries or chat text. The README lists the honest limits too, starting with first visit trust.
Some plugins have no UI at all and simply remove an annoyance:
The plugins are on npm under the @lucagiftzek scope, and each one also installs straight from GitHub. The sidebar tabs need dsh-better-sidebar, a community plugin that hosts them:
dsh plugin --profile web add dsh-better-sidebar # the tab host, skip if installed
dsh plugin --profile web add @lucagiftzek/dsh-artifacts
Swap in any other name: @lucagiftzek/dsh-mail, @lucagiftzek/dsh-phone, @lucagiftzek/dsh-voice and so on. Two exceptions: the Idle Watchdog is the unscoped dsh-idle-watchdog, and dsh-seal is not a plugin but a small Go service you clone and build (its README has the three lines).
Every README starts with its own install block and a screenshot, and links to the others. Tested on DSH 0.2.1; several also run on 0.1.5.
Each repo has issue templates and a security policy. If one of these saves you time, a star helps other DSH users find it. Everything is at https://github.com/lucagiftzek.