Exposes hermes --tui over a PTY-backed WebSocket so the dashboard can
embed the real TUI rather than reimplement its surface. The browser
attaches xterm.js to the socket; keystrokes flow in, PTY output bytes
flow out.
Architecture:
browser <Terminal> (xterm.js)
│ onData ───► ws.send(keystrokes)
│ onResize ► ws.send('\x1b[RESIZE:cols;rows]')
│ write ◄── ws.onmessage (PTY bytes)
▼
FastAPI /api/pty (token-gated, loopback-only)
▼
PtyBridge (ptyprocess) ── spawns node ui-tui/dist/entry.js ──► tui_gateway + AIAgent
Components
----------
hermes_cli/pty_bridge.py
Thin wrapper around ptyprocess.PtyProcess: byte-safe read/write on the
master fd via os.read/os.write (not PtyProcessUnicode — ANSI is
inherently byte-oriented and UTF-8 boundaries may land mid-read),
non-blocking select-based reads, TIOCSWINSZ resize, idempotent
SIGHUP→SIGTERM→SIGKILL teardown, platform guard (POSIX-only; Windows
is WSL-supported only).
hermes_cli/web_server.py
@app.websocket("/api/pty") endpoint gated by the existing
_SESSION_TOKEN (via ?token= query param since browsers can't set
Authorization on WS upgrades). Loopback-only enforcement. Reader task
uses run_in_executor to pump PTY bytes without blocking the event
loop. Writer loop intercepts a custom \x1b[RESIZE:cols;rows] escape
before forwarding to the PTY. The endpoint resolves the TUI argv
through a _resolve_chat_argv hook so tests can inject fake commands
without building the real TUI.
Tests
-----
tests/hermes_cli/test_pty_bridge.py — 12 unit tests: spawn, stdout,
stdin round-trip, EOF, resize (via TIOCSWINSZ + tput readback), close
idempotency, cwd, env forwarding, unavailable-platform error.
tests/hermes_cli/test_web_server.py — TestPtyWebSocket adds 7 tests:
missing/bad token rejection (close code 4401), stdout streaming,
stdin round-trip, resize escape forwarding, unavailable-platform ANSI
error frame + 1011 close, resume parameter forwarding to argv.
96 tests pass under scripts/run_tests.sh.
(cherry picked from commit 29b337bca7)
feat(web): add Chat tab with xterm.js terminal + Sessions resume button
(cherry picked from commit 3d21aee8 by emozilla, conflicts resolved
against current main: BUILTIN_ROUTES table + plugin slot layout)
fix(tui): replace OSC 52 jargon in /copy confirmation
When the user ran /copy successfully, Ink confirmed with:
sent OSC52 copy sequence (terminal support required)
That reads like a protocol spec to everyone who isn't a terminal
implementer. The caveat was a historical artifact — OSC 52 wasn't
universally supported when this message was written, so the TUI
honestly couldn't guarantee the copy had landed anywhere.
Today every modern terminal (including the dashboard's embedded
xterm.js) handles OSC 52 reliably. Say what the user actually wants
to know — that it copied, and how much — matching the message the
TUI already uses for selection copy:
copied 1482 chars
(cherry picked from commit a0701b1d5a)
docs: document the dashboard Chat tab
AGENTS.md — new subsection under TUI Architecture explaining that the
dashboard embeds the real hermes --tui rather than rewriting it,
with pointers to the pty_bridge + WebSocket endpoint and the rule
'never add a parallel chat surface in React.'
website/docs/user-guide/features/web-dashboard.md — user-facing Chat
section inside the existing Web Dashboard page, covering how it works
(WebSocket + PTY + xterm.js), the Sessions-page resume flow, and
prerequisites (Node.js, ptyprocess, POSIX kernel / WSL on Windows).
(cherry picked from commit 2c2e32cc45)
feat(tui-gateway): transport-aware dispatch + WebSocket sidecar
Decouples the JSON-RPC dispatcher from its I/O sink so the same handler
surface can drive multiple transports concurrently. The PTY chat tab
already speaks to the TUI binary as bytes — this adds a structured
event channel alongside it for dashboard-side React widgets that need
typed events (tool.start/complete, model picker state, slash catalog)
that PTY can't surface.
- `tui_gateway/transport.py` — `Transport` protocol + `contextvars` binding
+ module-level `StdioTransport` fallback. The stdio stream resolves
through a lambda so existing tests that monkey-patch `_real_stdout`
keep passing without modification.
- `tui_gateway/ws.py` — WebSocket transport implementation; FastAPI
endpoint mounting lives in hermes_cli/web_server.py.
- `tui_gateway/server.py`:
- `write_json` routes via session transport (for async events) →
contextvar transport (for in-request writes) → stdio fallback.
- `dispatch(req, transport=None)` binds the transport for the request
lifetime and propagates it to pool workers via `contextvars.copy_context`
so async handlers don't lose their sink.
- `_init_session` and the manual-session create path stash the
request's transport so out-of-band events (subagent.complete, etc.)
fan out to the right peer.
`tui_gateway.entry` (Ink's stdio handshake) is unchanged externally —
it falls through every precedence step into the stdio fallback, byte-
identical to the previous behaviour.
feat(web): ChatSidebar — JSON-RPC sidecar next to xterm.js terminal
Composes the two transports into a single Chat tab:
┌─────────────────────────────────────────┬──────────────┐
│ xterm.js / PTY (emozilla #13379) │ ChatSidebar │
│ the literal hermes --tui process │ /api/ws │
└─────────────────────────────────────────┴──────────────┘
terminal bytes structured events
The terminal pane stays the canonical chat surface — full TUI fidelity,
slash commands, model picker, mouse, skin engine, wide chars all paint
inside the terminal. The sidebar opens a parallel JSON-RPC WebSocket
to the same gateway and renders metadata that PTY can't surface to
React chrome:
• model + provider badge with connection state (click → switch)
• running tool-call list (driven by tool.start / tool.progress /
tool.complete events)
• model picker dialog (gateway-driven, reuses ModelPickerDialog)
The sidecar is best-effort. If the WS can't connect (older gateway,
network hiccup, missing token) the terminal pane keeps working
unimpaired — sidebar just shows the connection-state badge in the
appropriate tone.
- `web/src/components/ChatSidebar.tsx` — new component (~270 lines).
Owns its GatewayClient, drives the model picker through
`slash.exec`, fans tool events into a capped tool list.
- `web/src/pages/ChatPage.tsx` — split layout: terminal pane
(`flex-1`) + sidebar (`w-80`, `lg+` only).
- `hermes_cli/web_server.py` — mount `/api/ws` (token + loopback
guards mirror /api/pty), delegate to `tui_gateway.ws.handle_ws`.
Co-authored-by: emozilla <emozilla@nousresearch.com>
refactor(web): /clean pass on ChatSidebar + ChatPage lint debt
- ChatSidebar: lift gw out of useRef into a useMemo derived from a
reconnect counter. React 19's react-hooks/refs and react-hooks/
set-state-in-effect rules both fire when you touch a ref during
render or call setState from inside a useEffect body. The
counter-derived gw is the canonical pattern for "external resource
that needs to be replaceable on user action" — re-creating the
client comes from bumping `version`, the effect just wires + tears
down. Drops the imperative `gwRef.current = …` reassign in
reconnect, drops the truthy ref guard in JSX. modelLabel +
banner inlined as derived locals (one-off useMemo was overkill).
- ChatPage: lazy-init the banner state from the missing-token check
so the effect body doesn't have to setState on first run. Drops
the unused react-hooks/exhaustive-deps eslint-disable. Adds a
scoped no-control-regex disable on the SGR mouse parser regex
(the \\x1b is intentional for xterm escape sequences).
All my-touched files now lint clean. Remaining warnings on web/
belong to pre-existing files this PR doesn't touch.
Verified: vitest 249/249, ui-tui eslint clean, web tsc clean,
python imports clean.
chore: uptick
fix(web): drop ChatSidebar tool list — events can't cross PTY/WS boundary
The /api/pty endpoint spawns `hermes --tui` as a child process with its
own tui_gateway and _sessions dict; /api/ws runs handle_ws in-process in
the dashboard server with a separate _sessions dict. Tool events fire on
the child's gateway and never reach the WS sidecar, so the sidebar's
tool.start/progress/complete listeners always observed an empty list.
Drop the misleading list (and the now-orphaned ToolCall primitive),
keep model badge + connection state + model picker + error banner —
those work because they're sidecar-local concerns. Surfacing tool calls
in the sidebar requires cross-process forwarding (PTY child opens a
back-WS to the dashboard, gateway tees emits onto stdio + sidecar
transport) — proper feature for a follow-up.
feat(web): wire ChatSidebar tool list to PTY child via /api/pub broadcast
The dashboard's /api/pty spawns hermes --tui as a child process; tool
events fire in the python tui_gateway grandchild and never crossed the
process boundary into the in-process WS sidecar — so the sidebar tool
list was always empty.
Cross-process forwarding:
- tui_gateway: TeeTransport (transport.py) + WsPublisherTransport
(event_publisher.py, sync websockets client). entry.py installs the
tee on _stdio_transport when HERMES_TUI_SIDECAR_URL is set, mirroring
every dispatcher emit to a back-WS without disturbing Ink's stdio
handshake.
- hermes_cli/web_server.py: new /api/pub (publisher) + /api/events
(subscriber) endpoints with a per-channel registry. /api/pty now
accepts ?channel= and propagates the sidecar URL via env. start_server
also stashes app.state.bound_port so the URL is constructable.
- web/src/pages/ChatPage.tsx: generates a channel UUID per mount,
passes it to /api/pty and as a prop to ChatSidebar.
- web/src/components/ChatSidebar.tsx: opens /api/events?channel=, fans
tool.start/progress/complete back into the ToolCall list. Restores
the ToolCall primitive.
Tests: 4 new TestPtyWebSocket cases cover channel propagation,
broadcast fan-out, and missing-channel rejection (10 PTY tests pass,
120 web_server tests overall).
fix(web): address Copilot review on #14890
Five threads, all real:
- gatewayClient.ts: register `message`/`close` listeners BEFORE awaiting
the open handshake. Server emits `gateway.ready` immediately after
accept, so a listener attached after the open promise could race past
the initial skin payload and lose it.
- ChatSidebar.tsx: wire `error`/`close` on the /api/events subscriber
WS into the existing error banner. 4401/4403 (auth/loopback reject)
surface as a "reload the page" message; mid-stream drops surface as
"events feed disconnected" with the existing reconnect button. Clean
unmount closes (1000/1001) stay silent.
- web-dashboard.md: install hint was `pip install hermes-agent[web]` but
ptyprocess lives in the `pty` extra, not `web`. Switch to
`hermes-agent[web,pty]` in both prerequisite blocks.
- AGENTS.md: previous "never add a parallel React chat surface" guidance
was overbroad and contradicted this PR's sidebar. Tightened to forbid
re-implementing the transcript/composer/PTY terminal while explicitly
allowing structured supporting widgets (sidebar / model picker /
inspectors), matching the actual architecture.
- web/package-lock.json: regenerated cleanly so the wterm sibling
workspace paths (extraneous machine-local entries) stop polluting CI.
Tests: 249/249 vitest, 10/10 PTY/events, web tsc clean.
refactor(web): /clean pass on ChatSidebar events handler
Spotted in the round-2 review:
- Banner flashed on clean unmount: `ws.close()` from the effect cleanup
fires `close` with code 1005, opened=true, neither 1000 nor 1001 —
hit the "unexpected drop" branch. Track `unmounting` in the effect
scope and gate the banner through a `surface()` helper so cleanup
closes stay silent.
- DRY the duplicated "events feed disconnected" string into a local
const used by both the error and close handlers.
- Drop the `opened` flag (no longer needed once the unmount guard is
the source of truth for "is this an expected close?").
Crash-log stack trace (tui_gateway_crash.log) from the user's session
pinned the regression: SIGPIPE arrived while main thread was blocked on
for-raw-in-sys.stdin — i.e., a background thread (debug print to stderr,
most likely from HERMES_VOICE_DEBUG=1) wrote to a pipe whose buffer the
TUI hadn't drained yet, and SIG_DFL promptly killed the process.
Two fixes that together restore CLI parity:
- entry.py: SIGPIPE → SIG_IGN instead of the _log_signal handler that
then exited. With SIG_IGN, Python raises BrokenPipeError on the
offending write, which write_json already handles with a clean exit
via _log_exit. SIGTERM / SIGHUP still route through _log_signal so
real termination signals remain diagnosable.
- hermes_cli/voice.py:_debug: wrap the stderr print in a BrokenPipeError
/ OSError try/except. This runs from daemon threads (silence callback,
TTS playback, beep), so a broken stderr must not escape and ride up
into the main event loop.
Verified by spawning the gateway subprocess locally:
voice.toggle status → 200 OK, process stays alive, clean exit on
stdin close logs "reason=stdin EOF" instead of a silent reap.
SIG_DFL for SIGPIPE means the kernel reaps the gateway subprocess the
instant a background thread (TTS playback, silence callback, voice
status emitter) writes to a stdout the TUI stopped reading — before
the Python interpreter can run excepthook, threading.excepthook,
atexit, or the entry.py post-loop _log_exit.
Replace the three SIG_DFL / SIG_IGN bindings with a _log_signal
handler that:
- records which signal (SIGPIPE / SIGTERM / SIGHUP) fired and when;
- dumps the main-thread stack at signal delivery AND every live
thread's stack via sys._current_frames — the background-thread
write that provoked SIGPIPE is almost always visible here;
- writes everything to ~/.hermes/logs/tui_gateway_crash.log and prints
a [gateway-signal] breadcrumb to stderr so the TUI Activity surfaces
it as well.
SIGINT stays ignored (TUI handles Ctrl+C for the user).
Gateway exits weren't reaching the panic hook because entry.py calls
sys.exit(0) on broken stdout — clean termination, no exception. That
left "gateway exited" in the TUI with zero forensic trail when pipe
breaks happened mid-turn.
Entry.py now tags each exit path — startup-write failure, parse-error-
response write failure, per-method response write failure, stdin EOF —
with a one-line entry in ~/.hermes/logs/tui_gateway_crash.log and a
gateway.stderr breadcrumb. Includes the JSON-RPC method name on the
dispatch path, which is the only way to tell "died right after handling
voice.toggle on" from "died emitting the second message.complete".
The stdin-read loop in entry.py calls handle_request() inline, so the
five handlers that can block for seconds to minutes
(slash.exec, cli.exec, shell.exec, session.resume, session.branch)
freeze the dispatcher. While one is running, any inbound RPC —
notably approval.respond and session.interrupt — sits unread in the
pipe buffer and lands only after the slow handler returns.
Route only those five onto a small ThreadPoolExecutor; every other
handler stays on the main thread so the fast-path ordering is
unchanged and the audit surface stays small. write_json is already
_stdout_lock-guarded, so concurrent response writes are safe. Pool
size defaults to 4 (overridable via HERMES_TUI_RPC_POOL_WORKERS).
- add _LONG_HANDLERS set + ThreadPoolExecutor + atexit shutdown
- new dispatch(req) function: pool for long handlers, inline for rest
- _run_and_emit wraps pool work in a try/except so a misbehaving
handler still surfaces as a JSON-RPC error instead of silently
dying in a worker
- entry.py swaps handle_request → dispatch
- 5 new tests: sync path still inline, long handlers emit via stdout,
fast handler not blocked behind slow one, handler exceptions map to
error responses, non-long methods always take the sync path
Manual repro confirms the fix: shell.exec(sleep 3) + terminal.resize
sent back-to-back now returns the resize response at t=0s while the
sleep finishes independently at t=3s. Before, both landed together
at t=3s.
Fixes#12546.