dsh-session-tree-extension

dsh-session-tree

Append-only, multi-branch conversation trees for
DeepSeek-Harness — fork any
historical node, clone a branch into a new session, and browse the whole
lineage as one merged WebUI graph. Old history is never edited or deleted.

Three commands:

Screenshots

Tree panel (light and dark) with the sidebar's inline fork-branch menu:

The inline /fork branch menu beneath its source session:

Published as four npm packages under the @robiteame scope:

Install (users)

One command — from the plugin market UI, or from a Harness checkout's CLI:

dsh plugin --profile <profile> add @robiteame/dsh-session-tree

Prebuilt tarballs install the same way and need no build scripts:

dsh plugin --profile <profile> add robiteame-dsh-session-tree-0.6.0.tgz

After installing, restart the profile. The composition gains three rows
(pi-agent-session-tree, tool-session-tree, ui-session-tree) that load the
Host service, the commands, and the browser panel. Verify the composed layer:

dsh --profile <profile> --dump-config   # should list the three session-tree rows

Requires DeepSeek-Harness 0.2.1-alpha.2 (or a compatible 0.2.1 build) and
Cordis ~4.0.5-alpha.1; the target installation provides those peers. No install
scripts run — the tarballs ship prebuilt lib/ artifacts.

The three commands

/tree — open the tree panel

/tree opens the right-side panel as one merged graph for the current
session's lineage: ancestors, forks, and clones appear in a single git-style
view, with user messages, assistant replies, tool calls, and model switches
shown as connected nodes. Shared copied prefixes are deduplicated, fork points
carry session badges, and the current session's path stays highlighted. Click
a node to bind it; clicking a node owned by another session opens that session
first. Collapse individual subtrees or whole session branches to focus the
graph.

/fork — branch from any historical node

/fork picks an earlier user prompt and grows a new branch from there: the
conversation continues along the new path while the original one stays intact.
The fork is created through the official native fork API, so it appears in the
session list with real parent linkage. The plugin adds the new branch to the
merged graph and also renders it as an inline collapsible menu directly beneath
its source session's row. Both views follow the official reactive session list,
so new branches appear without a refresh.

/clone — duplicate into a new session

/clone copies the current conversation — through its root path — into an
independent Session under the same project. The source history stays
read-only; the clone is yours to continue separately.

Branch switching and graceful degradation

The plugin never modifies Harness core files. It capability-detects the
optional branch-selection engine API at runtime:

• Native mode — on a checkout carrying
  dev/session-branch-surface.patch
  (Session.selectMessageSurface()), jump/fork switch the model-visible
  history directly: the next turn genuinely starts from the new branch.
• Stock mode — on an unmodified official Harness, the plugin emulates the
  switch through official append APIs (an empty replace surface event) plus a
  plugin-owned sidecar under $DSH_HOME/storages/session-tree/ for durable
  branch state. The log stays resume-valid.
• Projection mode — if even the emulation is unavailable, navigation moves
  the tree projection and panel only, and the next turn keeps the canonical
  history.

Every mode is honest about itself: the Host log prints a one-time notice when
a session runs in a non-native mode. Move the raw session.jsonl.zstd between
machines together with the matching sidecar file.

How it works

• Append-only — every node is immutable; branching and jumping only move
  the cursor. Old branches are never edited or deleted.
• Every entry is a node — messages, tool calls, model switches, compaction
  records, and branch summaries all become typed nodes; each has a unique
  nodeId and a parentId (root is null). A node may have multiple
  children — that is the fork.
• Cursor navigation — jumping moves the active leaf to a historical node;
  the next append grows a new branch from there. Sibling branches stay intact.
• LLM context — the model always receives the standard messages array
  for the root→cursor path only.

Development (contributors)

The repository is a pnpm workspace building the three implementation packages
standalone (no Harness checkout needed):

pnpm install
pnpm verify      # build + typecheck (host & client) + pack dry-run + vitest
pnpm pack:all    # produce the four tarballs

Tests run against the published Harness packages (0.2.1-alpha.2) — the
stock-mode paths — with vitest from the repository root. The browser spec in
packages/client/ui-session-tree exercises both the 0.2 native right-Sidebar
registration and the older overlay fallback in the standalone suite.

Source integration against a Harness checkout

For debugging against a 0.2.1-alpha.2 Harness source checkout (native branch switching and source integration):

dev/install.sh /path/to/deepseek-harness     # applies both dev patches + copies packages
cd /path/to/deepseek-harness && pnpm install && pnpm run build

See dev/README.md for what each patch does. This flow is
for contributors only — user installs never touch a Harness checkout.

License

MIT.