dsh-viewer

The built-in read_image tool in DeepSeek Harness feeds a picture into the model context, but the human in front of the screen sees one line of text: a filename and a byte count. Video, audio, PDF, Office documents, local web pages — media a browser plays natively — get no card at all in the web UI. dsh-viewer inverts that. Its entire purpose is to put a file on your screen.

It covers 36 file extensions across six render kinds: images with a click-to-zoom lightbox, seekable video and audio players with real scrub bars, an embedded PDF viewer, Word / Excel / PowerPoint / ODF documents converted on the host via LibreOffice and embedded as PDF, and local HTML pages running inside a sandboxed iframe. A signed HTTP asset route with Range request support makes even a two-hour video fully seekable; HMAC path signing, Content-Security-Policy sandboxes, and nosniff headers form layered security boundaries that survive session-log replay.

If you run multimodal tasks in Harness daily and are tired of "the file is here" followed by a single line of metadata, or if you want the model to see the image while you see it too, this plugin is built for that. One display_file call does both: you get a fully rendered player on screen, and the model receives pixel data in its context.