tvision

A character-cell window manager for DeepSeek Harness agents. Overlapping framed windows on a textured desktop, a Borland menu bar, a function-key strip, mouse dragging, and five skins — installed as an ordinary dsh profile bundle, not a fork.

The blue your hands remember from Turbo C — and four more looks ship in the same binary:

Amber CRT	Phosphor	Slate	ANSI (One Dark style)

  File  View  Agent  Tools  Window  Help                        dsh tvision
╔═════════════════════════ Conversation ═════════════════════════╗┌───── Project ──────┐
║> You                                                            ║  o src/parser.ts   │
║  why is the first token so slow?                                ║  o src/stream.ts   │
║                                                                 ║  o README.md       │
║| Agent · 1.4s                                                   ║                    │
║  The parser buffers the whole document before it emits          ║                    │
║  anything, which is why the first token never arrives until     ║                    │
║  the whole file is read.                                        ║                    │
║                                                                 ║                    │
║~ bash  npm test -- parser                                       ║┌────── Tasks ───────┐
║  ok ▸                                                           ║  ✓ Find why it is  │
║                                                                 ║  ▸ Make the parser │
║─────────────────────────────────────────────────────────────────║  · Update the test │
║dsh> refactor it so it streams                                   ║                    │
╚═════════════════════════════════════════════════════════════════╝  ░░░░░░░░░░░░░░░░░░░
             │ F10 menu │ 3 win │ ████░░ 62% │ ↑12.4k ↓3.1k │ deepseek-flash
F1 Help      F2 New       F3 Open      F4 Tools     F5 Focus     F6 Next      F7 Project

English | 中文

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Try it without an agent

No key, no profile, no network. The demo drives the real desktop with a scripted agent:

npm install
npm run build
node lib/demo.js                 # the Turbo Vision blue
node lib/demo.js --skin amber    # P3 amber CRT
node lib/demo.js --list-skins

Type anything and press Enter to replay the script; F1 lists the keys and F10 opens the menu.

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Install as a dsh profile

Requires Node ^22.19 || >=24 and the dsh CLI.

git clone https://github.com/hongxin/dsh-tvision
cd dsh-tvision && npm install && npm run build
dsh plugin --profile tvision add "$(pwd)"
dsh --profile tvision                                    # start in the current directory
dsh --profile tvision --resume <session-id>              # resume a persisted session
dsh --profile tvision --skin amber --no-mouse            # start options

Once the package is published to npm, the clone-and-build steps collapse to dsh plugin --profile tvision add dsh-tvision.

Set DEEPSEEK_API_KEY in the environment, or in a .env in the launch directory or $DSH_HOME. A local or self-hosted endpoint needs no code change — point DEEPSEEK_BASE_URL at it, or set llm-deepseek.baseURL in $DSH_HOME/settings.yaml.

Status. Verified: the desktop mounts against a real dsh --profile tvision agent and draws in a real terminal (python3 scripts/pty-profile.py); the full stack — streaming, reasoning, approvals, tool round trips — runs end to end against a scripted model endpoint (python3 scripts/pty-wire.py); the standalone demo passes an 18-scenario real-terminal sweep with zero invariant defects; and live model turns have been run against the real API. The golden corpus is hand-written synthetic content pinned to real event shapes — real transcripts are never committed. See the design doc's scope section.

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Keys

Always

Key	Action
F1	Help — the full key list and the mouse reference
F2	New session
F3	Sessions window
F4	Expand / collapse every tool card
F5	Focus the composer
F6	Next window
F7	Project window — choosing a file references it in the composer
F8	Tasks window
F9	Cycle skin
F10	Menu bar
Ctrl+Q	Quit
Ctrl+C	Cancel the current turn
Ctrl+O	Expand / collapse tool cards
Ctrl+R	Show / hide the agent's reasoning
Ctrl+Z	Zoom the focused window
Ctrl+F	Search the transcript — Enter next hit, Shift+Enter previous, Esc back where you were
Ctrl+L	Redraw the screen

Menus

F10 enters the menu bar; ←/→ walk it and ↓ opens a list. Alt plus the underlined letter opens a menu directly, and the same letter inside an open list invokes the item.

Composer

Key	Action
Enter	Send
Alt+Enter	Insert a newline instead of sending
Tab	Complete a /command or an @file
↑ / ↓	Walk the input history
Ctrl+A / Ctrl+E	Start / end of line
Ctrl+U / Ctrl+K	Delete to the start / end
Ctrl+W	Delete the previous word

Transcript

Key	Action
PageUp / PageDown	Scroll a page
↑ / ↓	Scroll a line
Home / End	Jump to the start / end

Scrolling away from the end stops new output from pulling you back down. End re-arms it.

Sessions and Jobs

Key	Action
type	Filter the Sessions list — title, workspace, or id
Backspace / Esc	Edit / clear the filter
k	Kill the selected job (asks first)
Enter	Resume the session / describe the job

Without a configured API key the status line says so, and Tools ▸ API key… collects one into $DSH_HOME/.credentials.yaml — the key is never echoed back after entry. External edits to the workspace reach the Project window on their own now; no tool needs to run first.

Mouse

Drag a title bar to move a window · drag the bright bottom-right corner to resize · click [■] to close · click [↑] or double-click a title to zoom · wheel-scroll whatever the pointer is over, including the function-key strip.

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Skins

--skin
tvision	Turbo Vision — the Borland blue: cyan frames on a dark blue desktop
phosphor	P1 green CRT — one hue, brightness carries the hierarchy
amber	P3 amber — warmer, easier for long sessions
slate	Modern dark — the window manager without the costume
ansi	A One-Dark-style editor palette in your terminal's own sixteen colours

Each skin is a complete set of ~55 semantic roles rather than a palette swap, so any skin that renders one widget legibly renders them all.

The installed default is tvision — the Borland blue is the whole point; --skin ansi (or F9) follows your terminal's own theme. The standalone demo keeps tvision as its showcase.

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Why

The short version: an agent is a good fit for a text-mode IDE. Its activity is already a stream of file edits, shell commands, diffs, task lists, and subagents — which is what Borland built this interface for, minus the debugger.

This is not a chat TUI with a border. It is a window manager:

• Overlapping windows with drop shadows, because depth should be legible before you read a word.
• A double-line active frame and single-line inactive ones, so you can see where the keyboard is going from across the room.
• A menu bar above all windows, so no capability is keyboard-only folklore.
• A function-key strip generated from the keymap, so the legend cannot lie about the keys.
• A fixed single-line composer, because a growing input box shoves the conversation around.
• Modal dialogs as real windows, so an approval prompt gets the same keyboard, mouse, and focus handling as everything else.

The transcript has a one-character gutter — > you, | the agent, · reasoning, ~ a tool, ! an error — so the shape of a conversation is visible before its words are. Tool calls are one line collapsed and a framed body expanded, with colour-coded diffs.

Read docs/DESIGN.md for the full reasoning, the architecture, and what is deliberately not finished.

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Development

Until the package is published, install the working tree into the profile as a linked directory (the profile then runs whatever lib/ is currently built):

dsh plugin --profile tvision add "$(pwd)"
python3 scripts/pty-profile.py --profile tvision   # non-interactive mount check

npm install
npm run typecheck     # tsc --noEmit
npm test              # 505 tests
npm run build         # bundles lib/
npm run demo          # the demo

The tests are worth a note. tests/compositor.spec.ts paints frames and replays the bytes into a real terminal emulator (xterm.js headless), then compares the resulting grid cell for cell — which is the only way to catch a rendering bug that is invisible in the escape strings. tests/snapshot.spec.ts checks in whole-desktop frames as ASCII, so a reader can see the entire interface in a diff:

Tvision_SNAPSHOT=refresh npx vitest run tests/snapshot.spec.ts

Verifying in a real terminal

The emulator proves the escapes produce the grid we think they do. It cannot prove a real terminal agrees, and it cannot reach the interactive paths at all. So there is a pty harness for that:

# Drive the demo under a real pty, typing and dragging at it.
python3 scripts/pty-drive.py '{"argv":["node","lib/demo.js"],"columns":104,"rows":30,"timeout":8}' > /tmp/capture.bin

# Read back what the real terminal had on screen.
npm run verify:pty -- /tmp/capture.bin 104 30

It is how the mouse drag, the menu dropdown, the help window, and the truecolour palette were confirmed on a real screen rather than an emulated one.

scripts/pty-sweep.py drives a matrix of sizes and key sequences and checks the invariants a terminal enforces silently — no row written past the edge, no frame that scrolls the screen, chrome that has not drifted:

python3 scripts/pty-sweep.py --json .tools/sweep.json   # needs a pty
npx vitest run tests/sweep.spec.ts                      # check the captures

It reads .tools/sweep.json and skips itself when that file is absent, so the suite stays green on a machine that cannot allocate a pty.

Found a bug?

Run the report tool, use tvision as you normally would, then quit with Ctrl+Q:

python3 scripts/tv-report.py

It writes .tools/report-<timestamp>.txt holding your terminal's size, the environment the app read, the final screen replayed as text, and the raw byte stream — which is enough to see the bug without a description of it. Ctrl+C exits the tool early.

Layout

src/kit/        cell · text · styles · screen · painter · widget · wm · input · skin
src/session/    the retained document
src/views/      transcript · dialogs
src/widgets/    frame · menubar · statusbar
src/app/        app · composer · questions · events · project · sessions
src/term/       the real terminal

kit/ imports nothing above it and knows nothing about agents; it would work as a general text-mode windowing library.

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Credits

MIT. The implementation is original; the integration follows the open-source DSH terminal front end that shipped in deepseek-harness before being removed upstream and recovered as @dsh-tui/dsh-tui (MIT, DeepSeek and OpenGuardrails) — the Cordis plugin shape, the session-event fold's responsibilities, the waterfall seams for approvals and questions, and the approach to the test harness are all modelled on it. Reading it is also how the two API drifts it carries were found.

The interface owes its shape to Turbo Vision (Borland), Midnight Commander, and moc.