@hzpeng/dsh-lens-rail

A Codex-style LEFT message navigation rail for the DeepSeek Harness (DSH) Web conversation column.

A vertical column of short horizontal lines runs down the left edge of the transcript — one line per message, including both your turns and the agent's replies. It is a scroll-spy scrubber: the line under your current reading position is highlighted in the brand colour, hovering grows the line under the cursor while its neighbours taper smoothly toward the edges (the Codex "lens" effect), and clicking any line jumps the transcript to that message (paging older history when necessary).

Unlike @max-null/dsh-chat-rail (a right-side rail that expands into a titled/numbered panel on hover), this rail always stays a clean column of short lines and anchors to the left edge, matching the Codex (ChatGPT) app interaction.

Features

• Left edge placement — left: calc(var(--dsh-sidebar-width) + 4px), so it sits beside the conversation column and never overlaps the app sidebar.
• One line per message — both user turns (user nodes) and agent replies (assistant nodes) get a line; tool rows, commands, and turn-tails are skipped so the rail reads as a conversation, not a step ledger.
• Lens hover — the focused line is longest; neighbours taper off with a gaussian profile (width = base + amp * exp(-d²/2σ²)), exactly the Codex effect.
• Scroll-spy highlight — the line nearest the 40% viewport line is active (brand colour + glow) and follows your reading position.
• Click to jump — loadOlder pages older history on demand, then scrolls the target row into view; shows a small spinner while a long jump loads.
• Theme-aware — uses DSH alias tokens (--dsw-alias-*) so light and dark themes both look right.

How it works

This is a pure client plugin. The host half is an intentionally empty apply — it exists only so the Loader registers the entry and the client-modules scanner discovers the dsh.client declaration + ./client bundle.

The client half reads data directly from the session snapshot's chat nodes. Every chat node carries a .key equal to the data-chat-anchor-key the chat view stamps on its DOM row, so that same key drives all three concerns:

• scroll-spy — scan [data-conversation-scroll] rows for the one nearest the reading line;
• hover hit — each line is a `` with data-lens-index;
• click-to-jump — jumpToMessage loops loadOlder() until the target node exists, then polls for its DOM row and scrollIntoViews it.

No host projection, no session-log fold, no model-visible context, no tool registered.

Install

The plugin mounts through a cordis.patch.yml insert and must resolve from the profile's dependency tree ($DSH_HOME/profiles/node_modules).

# from the plugin directory, add it to your web profile's dependencies
# $DSH_HOME/profiles/web/package.json
#   "dependencies": { "@hzpeng/dsh-lens-rail": "file:../../workspace/dsh-lens-rail" }

# then mount it
# $DSH_HOME/profiles/web/cordis.patch.yml
#   - insert:
#       - id: dsh-lens-rail
#         name: '@hzpeng/dsh-lens-rail'

Restart dsh web and hard-refresh the browser. The client bundle is served runtime from /plugins/dsh-lens-rail/client.js, so no rebuild of the DSH web shell is needed — only a process restart to pick up the new loader entry.

Alternatively use the built-in installer:

dsh plugin --profile web add @hzpeng/dsh-lens-rail

Uninstall

Remove the - insert: { id: dsh-lens-rail, ... } block from $DSH_HOME/profiles/web/cordis.patch.yml and drop the dependency from package.json, then restart dsh web.

License

MIT