dsh-t3-session-ui

T3 Code's session-context UX for DeepSeek Harness: a session-row context block, provider/model chip, a status pill, a per-session header context strip, and a context-window meter that can compact.

Credit

The information hierarchy this plugin implements is T3 Code's: the session-row hover card, the status ladder, the provider/model row, and the context-window ring with its compaction action are all theirs. T3 Code is open source under MIT; this port keeps the same shape and swaps the data underneath for DeepSeek Harness's. Please support the original project.

What it adds

Every surface reads one per-session context bundle from this package's own Host half. A fact the Host could not read is omitted rather than faked, so a session outside a git work tree simply has no branch row.

Surface	Seat	Shows
Row hover card	sidebar.session.row.hover	Status, machine, workspace, branch (+ dirty), worktree, model · provider, agent preset, parent session, approval policy, context usage, and the error line
Row chip	sidebar.session.row.leading	The model as the row's leading cell, with a status dot
Header strip	conversation.session.header.utilities	Status, model, branch, workspace, approval policy, subagent count, preset, delegation depth
Context ring	conversation.input.activity	Context-window percentage as a ring (red past 90%) that expands into a panel with token counts, a progress bar, and a Compact button
Copy action	conversation.session.header.actions	Copy the whole context bundle as JSON
Row menu items	sidebar.workspaces.session.menu.item	Copy context as JSON, copy branch name, copy working directory

The context ring occupies conversation.input.activity, which is empty in a stock DSH — it adds a control rather than replacing a shipped one. It expands across the composer's toolbar while open, using the seat's onActiveChange handoff. The Compact button runs DSH's own /compact command; this plugin never reimplements compaction.

Install

dsh plugin --profile desktop add dsh-t3-session-ui

Or from a checkout, which needs no build step:

dsh plugin --profile desktop add /path/to/dsh-t3-session-ui

Removing the bundle unregisters every seat and restores the previous composer toolbar with no residue.

How it works

The facts this UI shows are not reachable from the browser — the machine identity is a node:os call, and sessions, tokenMeter, approval, and compaction carry no @Remote face, so a Client half cannot call them through ctx.remote. The Host half therefore serves one fenced JSON RPC route:

POST /t3session/api/hostFacts        -> machine identity, no session needed
POST /t3session/api/sessionContext   -> { sessionId } -> the context bundle
POST /t3session/api/compact          -> { sessionId } -> runs /compact

The route is fenced to loopback (plus any authority the deployment declares trusted), rejects cross-site browser markers, and requires a matching Origin when one is present. A browser page therefore reaches it with a plain relative fetch, the same bridge dsh-better-sidebar and @michengai/dsh-codex-ui use.

Where each fact comes from:

Fact	Source
Machine label	os.hostname(), prettified (Shimas-MacBook-Pro.local → Shima's MacBook Pro), overridable by config
Working directory, preset, parent session, delegation depth	Session.header
Provider, model, context-window size	Session.requestContext()
Branch, dirty state, worktree	git run in the session's own directory, cached for 5s
Tokens used	ctx.tokenMeter.measure(session)
Turn state	The session's own turn/start / turn/end events
Subagent fan-out	ctx.subagents.listChildren(sessionId)
Approval policy	ctx.approval.overrideOf(session)

Status ladder, and one honest gap

T3 Code ranks pending approval and awaiting input above Working. DSH cannot report either from the Host: a pending approval and an awaiting-input prompt live in Client chat state that these seats do not receive, and neither appears in SessionSnapshot. So the ladder here is the observable subset — failed → working → subagent fan-out → ready — and the approval policy is reported as its own row rather than mislabelled as a pending request.

Configuration

- id: t3-session-ui
  name: 'dsh-t3-session-ui'
  config:
    machineLabel: "Shima's MacBook Pro"   # optional; defaults to the prettified hostname

Development

Plain ESM, no build step. The Client half is loaded as-is by DSH's client-module loader, so editing client.js takes effect on the next page load.

pnpm install
pnpm test        # 63 tests: host logic + static rendering of every surface

The tests run without DSH: the Client suite stubs window.__ModuleLoader__ and renders each surface to static markup against a fixture bundle, and the Host suite exercises real temporary git repositories.

Requirements

• DSH 0.1.5-rc.1 or newer
• Node.js 20+

License

MIT. The ported design is T3 Code's, also MIT.