dsh-shot

Composer screenshot control for DeepSeek Harness: a camera button next to ＋ in the composer opens a two-item menu, and the capture is framed and annotated in an overlay inside the window (no fullscreen, the window stays where it is). The result lands in the current conversation's composer as an image attachment.

Windows only — the capture itself is a PowerShell child that drives Win32 (window lookup, hide/restore, DWM-aware screen grab).

Requirements

• DeepSeek Harness 0.1.7 or newer, desktop/web profile.
• Windows (the host half shells out to scripts/capture.ps1).
• Node ^22.19.0 || >=24.0.0.
• No runtime dependencies: the host half imports only node:* builtins.

Install

# from a checkout
dsh plugin --profile <profile> add ./dsh-shot

# from a packed tarball
pnpm pack
dsh plugin --profile <profile> add ./dsh-shot-0.1.0.tgz

# from npm (once published)
dsh plugin --profile <profile> add dsh-shot

A package that declares dsh.bundle is appended to dsh.profile.bundles automatically, so the layer is composed on the next boot. Verify without booting:

dsh --profile <profile> --dump-config   # look for the "== dsh-shot" layer

Then restart the app — the client bundle URL carries a build revision that is computed at startup, so a page refresh is not enough for lib/client.js changes.

Use

1. Click the camera button next to ＋ in the composer and pick one of the two menu items.
2. The overlay appears covering the window: drag a box to select a region.
3. Annotate if you want, then confirm.

Annotation tools: rectangle, arrow, text (click a point, type, Enter to confirm, Esc to cancel; double-click existing text to edit it), an eight-colour palette, plus undo and reselect. Text carries a translucent dark plate so it stays readable on any background.

Confirming (or Enter) puts the image into the composer draft. It is an ordinary image attachment: you can preview it, add a message, and it is only sent when you send.

How it fits together

The client half is declared in package.json under dsh.client and is served from /plugins/dsh-shot/client.js.

Known limitations

• Windows only. The capture path is Win32 + DWM.
• The overlay covers the window, not the screen. The whole capture is scaled to fit and centred, so nothing is cropped and the entire screen stays visible; the leftover margin is a dark letterbox. On a 2560x1440 screen with a 1296x828 window that is about 50px top and bottom. The scaling is recomputed from the window size every time the overlay opens, so a different screen or window size needs no configuration.
• Multi-monitor is captured as one virtual screen; it is all visible, but a small window shows it small.
• The hide mode briefly makes the DSH window disappear (roughly 0.3–1.2 s).
• Rare: the capture script can return an almost empty frame (a few tens of KB instead of several MB). Re-running the capture succeeds; an automatic retry is not implemented yet.

Development

# static contract checks (patch, manifest, red lines)
dsh-plugin-dev check --cwd .

# pack + install/start/uninstall in a throwaway DSH_HOME
dsh-plugin-dev verify --cwd .

Headless regression suites for this plugin live outside the package, in dsh-screenshot-research/ (test-host.mjs, test-client.mjs, deliver-probe.mjs, e2e-shot.mjs); they drive a throwaway headless Edge with a self-signed session cookie and never touch a real browser profile.

DESIGN.md is the implementation and decision log: the measured evidence behind each design choice, and the traps that were already paid for.

License

MIT.