DSH Session Rail

A per-session right sidebar preview for DeepSeek Harness (DSH). It displays Environment, Context, Plugins, Output files, Git Changes, and Background tasks in that order.

Requirements

• DSH Web with the right-sidebar tab package available.
• Node.js >=22.19.0 on the DSH Host.

Build and install locally

From this package directory:

npm install
npm run typecheck
npm run build
dsh plugin --profile web add "file:$PWD"

Restart or reload the DSH Web profile if the plugin loader does not activate the new entry immediately. Remove it with:

dsh plugin --profile web remove session-rail

The Environment card shows the Session's project folder name, full path, and current Git branch. Context reads DSH token-meter projections (contextPressure, contextBreakdown, tokenUsage) and, when the optional dsh-context plugin is installed, the fine-grained contextTimeline projection. The panel shows a colored category occupancy bar, per-category shares, expandable assistant detail when present, timing/cache rows when the source provides them, and explicitly marks Claude-style categories that DSH does not expose (MCP instructions, Memory, and Skills when only the coarse meter is available). Plugin names and enabled/runtime status come from DSH's public read-only plugin inventory.

Output files lists files this Session's AI actually changed, grouped by turn with the newest turn first. Session Rail discovers each turn's workspace/changes event sequence by registering a uiConversation event definition that folds public workspace/changes and deliverables/presented events, then reads the Host summary from GET /api/changes.summary?sessionId=&seq=. Files explicitly delivered with present are included and marked Delivered / 「交付」. Clicking a changed file opens DSH's built-in changes-review tab through sidebarRight.openResource and changesReviewAddress (dsh-resource://changes-review/session/<sessionId>/<seq>/<turn>, with { params: { index } }). Clicking a delivered file opens a Sidebar preview via fileAddressFor(sessionId, cwd, path). If the Host was restarted and a summary no longer exists, the card shows that the summary is unavailable instead of inventing a 0-file count. A session with no announcements shows an empty state.

Changes lists the Session workspace's current Git working-tree files, staged/unstaged state, and line counts. Commit changes sends the fixed user message Commit the working tree changes with a sensible message. to that Session's live Agent. The Agent performs the commit through its normal tools; Session Rail never stages, commits, pushes, or mutates files itself.

Selecting a working-tree file opens the official changes-review tab on the latest turn whose summary lists that path. If the path is not in any recorded summary, Session Rail opens a Sidebar preview of the current file with fileAddressFor. It does not expand an inline raw unified diff, and it does not use codex-review as the default target. The Review page field remains as an optional override: when it is non-empty, Session Rail tries openTab(kind) first and then falls back to the official review or file preview if that kind cannot be opened. If openResource fails, a short status message is shown. The field still offers every active page tab published by the DSH sidebarRightTabs registry as a suggestion (resource-only types such as changes-review, which cannot be opened by kind, are omitted). The choice is stored in browser localStorage.

Background tasks sits below Changes and lists this Session's background jobs and sub-agents in one card. In-progress rows show a truncated title, a live elapsed time, and — for running jobs — a Stop control that follows the official two-step confirm: the first click arms it, and a second click within 3 seconds calls ctx.jobs.kill. Job rows come from the official ctx.jobs service (job.list via watchRows). This MVP does not draw a custom terminal or call job.follow. Sub-agents come from the session's public subagentCatalog projection, enriched with subagentTiming and running state from useSessions / useSessionStatus when those are available. Clicking a local sub-agent opens the official Sidebar chat at dsh-resource://subagentchat/session/<child>?parent=<parent>&mode=<mode>. External tasks are listed but are not navigable. Completed jobs and sub-agents fold behind “N finished” / 「已完成 N 项」. An empty session shows a short empty state; a catalog read failure shows an error instead of a fake zero count. The card is read-only except for Stop.

The sidebar tab is available from the right-sidebar tab picker and from the small button in the Session header. Switching Sessions uses that Session's own workspace, output-file announcements, background tasks, and context projections.