dsh-side-chat

A side chat for the DeepSeek Harness Web GUI: open the right sidebar from the session header, add the Side chat (「侧边会话」) tab, and keep the main conversation untouched — while the side conversation still carries the same agent, the same tools, and really edits the same workspace files.

English | 中文

Quick start

# npm (recommended)
dsh plugin --profile desktop add @flyer103/dsh-side-chat

# GitHub, default branch or a pinned tag
dsh plugin --profile desktop add github:flyer103/dsh-side-chat
dsh plugin --profile desktop add github:flyer103/dsh-side-chat#v0.6.0

# local checkout (records a link: dependency)
cd /path/to/dsh-side-chat
dsh plugin --profile desktop add "$(pwd)"

# tarball built with `npm pack`
dsh plugin --profile desktop add /absolute/path/flyer103-dsh-side-chat-0.6.0.tgz

Use the profile you actually run: desktop for the Desktop app, web for a web profile. Prefer quitting the Desktop app before installing into desktop (the CLI waits on the profile write lock) and reopen it afterwards; either way a restart is required. add also appends the bundle to the profile's dsh.profile.bundles; you do not edit the profile's cordis.patch.yml by hand. Re-running is safe.

Alternatively, from a local checkout:

node scripts/install.mjs --profile desktop            # idempotent; never restarts DSH
node scripts/install.mjs --profile desktop --dry-run  # show the plan only

Then restart DSH, open a session, and expand the right sidebar from the session header (「Open sidebar」 / 「打开侧边栏」). On the sidebar's guide page, click the 「Side chat」 (「侧边会话」) card; the side chat opens as a native tab in that column. (There is no session-header side-chat button and no floating overlay — the entry lives in the right sidebar, also reachable from the tab strip's add control; inside an open side-chat tab, the status bar's New side chat button opens another one.) Send the first message: that tab's side chat is created on that send and destroyed when you close its tab. Every click of the guide card, and every press of a tab's New side chat button, opens another side-chat tab in the same pane, each with its own side session and a chip numbered within the parent session (Side chat, Side chat 2, …; 「侧边会话」, 「侧边会话 2」…). Collapsing the sidebar or switching to another tab only pauses a side chat; opening a tab without sending costs nothing. Closing one side-chat tab destroys only that side chat — the other side chats and the main session are unaffected.

What it does

• Native sidebar tab — lives in the session's right sidebar next to the other tabs; no standalone session-header button and no floating overlay.
• Several at once — a parent session can hold multiple independent side-chat tabs, each its own ephemeral side session with a numbered chip; open another from the guide card or from a tab's New side chat button.
• Inherits context — the parent's completed turns plus a snapshot of what the main session is doing right now, taken when that side chat is created.
• Inherits the agent — same working directory, preset composition, tools, skills, model routing, sandbox mode and approval policy.
• Really edits files — write/edit/bash changes land in the same workspace and the main session sees them.
• Isolates the transcript — side-chat turns never appear in the main conversation, the session list, or the subagent catalog.
• Streams the reply — assistant text, reasoning and tool calls render token by token from a live event stream while the turn runs; when the transport cannot stream, the tab falls back to polling.
• Shows its own usage — a slim dock under the composer (the same spot as DSH's main composer dock) shows this side chat's total tokens, cache-hit percentage, and a small context-occupancy ring + percentage. Hover for the exact uncached-input, cache-read and output counts (plus a cache-write count when the provider reports one) and the approximate ~used / window pair. The dock starts hidden until the side chat has a usage sample, and it resets with each new side session.
• Destroys on close — closing a tab disposes that tab's side chat and the host tries to remove its persisted artifact; a closed side chat cannot be reopened, and the other side chats and the main session are unaffected. Collapsing the sidebar or switching tabs only pauses it.

Compatibility

• DSH 0.2.1-rc.2 (Desktop profile, Web GUI) — the tested target. This release was verified against a real dsh web process in an isolated DSH home with a fresh web profile: the plugin launches, all eight host routes answer (including the SSE route's JSON fallback), and the client bundle is served.
• No engines.dsh and no DSH peer dependency are declared, so DSH does not version-gate installation. That is separate from the tested version: newer DSH releases are untested.
• Web platform only (dsh.client.platform: web); no CLI/TUI surface.
• Node.js >= 22; the plugin itself is dependency-free ESM with no @deepseek-ai/* imports.
• UI copy follows the DSH language setting (Settings → General → Language): Chinese and English are built in, and any other language falls back to English. Technical details — host error messages, routes, event and tool names — stay in English.

Known limitations

• Approval prompts are not shown inside the side-chat tab: the side session inherits the parent's approval policy, and if that policy asks a human, the side session waits. Use a non-interactive policy (for example danger-full-access) for side chats that must write files.
• A closed tab cannot be restored: reopening the guide card or pressing New side chat starts a new side chat, whose agent is created on the next message.
• P1, designed but not implemented: model picker, surviving a GUI restart, approval rendering in the tab.
• The inherited context is a snapshot taken when that side chat is created; later main-session turns are not pushed into an existing side chat, and each side chat keeps its own snapshot.
• Token streaming rides on a streamable fetch response. If the page transport buffers the response (detected by a missing first frame), the tab falls back to snapshot polling: the running indicator returns and the reply still appears while it grows, at poll granularity.
• Each side chat's first request is roughly as large as the parent's next request (it carries the inherited history), so N concurrent side chats multiply that first-request cost.
• The usage dock is approximate and side-scoped: its token totals and cache-hit percentage cover what this side chat itself billed — its own requests, including the inherited context its first request re-sends — and never the parent's earlier requests; its context percentage is absolute for the same reason, and it omits DSH's projected-token correction, so it can trail the main composer's context bar by up to one step. It shows no turns, steps or tok/s, has no click-open dialogs, and cannot follow DSH's Performance & usage detailed/compact preference; its content is fixed.
• A reattached side-chat tab whose session log exceeds the 2000-entry snapshot page can undercount earlier usage in that dock. A tab that has watched the side chat since its first message is unaffected, because every committed event reaches it.

Documentation

• docs/USAGE.md — full semantics: inheritance, isolation, mutation, lifecycle, installation, rollback, troubleshooting.
• docs/DESIGN.md — scope, phases and adversarial notes.
• docs/CONTRACT.md — host routes, Sidebar tab integration and rendering contract.

Repository layout

path	role
lib/index.js	host half: routes, live attempt accumulation and the SSE stream, fork seed, boundary injection, per-instance session registry, close/dispose
lib/client.js	client half: right-Sidebar tab type + guide entry, the per-tab body (streaming messages + composer + usage dock), numbered tab chips, the new-side-chat button and the close handler
cordis.patch.yml	bundle patch inserting the dsh-side-chat row
scripts/install.mjs	idempotent installer/remover for a local checkout
dsh.plugin.json	community manifest metadata; DSH does not read it (official display metadata comes from package.json and optional locale/*.json)
tests/	node --test unit tests

Uninstall

dsh plugin --profile desktop remove @flyer103/dsh-side-chat

Then restart DSH. No transcript, schema or workspace data is migrated or deleted; side chats are ephemeral.

License

MIT