The pane, in-app browser, and reaction tools were gated on HERMES_DESKTOP=1 —
an env var set only on backends Electron spawns itself (local and SSH). A
desktop client connected to a plain URL gateway or Hermes Cloud lost all six:
they were stripped from the schema before the model saw them, on the same
backend whose platform hint was telling it "you are chatting inside the Hermes
desktop app". open_preview, read_preview, read_terminal, close_terminal,
focus_pane, and react_to_message were all silently absent.
The client is not the host. Capability now resolves from the session's own
source, which session.create already carries:
- The six tools move into a `desktop_ui` toolset, off _HERMES_CORE_TOOLS so no
other platform pays their schema.
- _gui_surface_toolsets(platform) folds `desktop_ui` (and the existing
`project` tools) into the GUI gateway's resolution when the session's
platform is the desktop app — the same answer on every topology.
- check_fn drops the env probe. It kept the one thing that is genuinely a
per-process/user fact: react_to_message's display.message_reactions opt-in,
which the desktop mirrors onto whichever gateway it is connected to.
react_to_message was doubly broken: it read that toggle behind the env gate, so
even a local-backend user's Settings toggle could not reach a remote session.
The embedded terminal pane keeps working correctly the other way round: it runs
`hermes --tui` against a desktop-spawned backend, and a tui-sourced session
gets no GUI tools even though HERMES_DESKTOP=1 is set on that process.
Extract the open_preview emitter into a shared tools/desktop_ui bridge
(one gateway-injected sink, routed by HERMES_UI_SESSION_ID) and add a
second desktop-gated tool on top of it:
- focus_pane(chat|files|terminal|review|sessions) -> pane.reveal event.
The desktop runs each pane's own reveal path (revealDesktopPane table)
and only acts on the active window -- a background turn never moves the
user's focus (desktop AGENTS.md: offer, don't hijack).
open_preview now emits through the same bridge. Both tools are check_fn
on HERMES_DESKTOP (zero footprint elsewhere), sitting beside
read_terminal/close_terminal in _HERMES_CORE_TOOLS.
Deliberately not adding run_slash: letting the agent fire slash commands
mid-turn (/model, /new, /clear) fights prompt-cache + conversation
invariants.
Add a desktop-gated open_preview tool so 'open cnn.com in the preview
pane' works. The tool (check_fn on HERMES_DESKTOP, zero footprint
elsewhere) emits a preview.open event through a gateway-injected emitter,
mirroring the close_terminal -> terminal.close bridge. The desktop
handles it in usePreviewRouting, normalizing the target and opening the
pane for the active session only -- a background turn never hijacks it.
Bare domains and localhost are coaxed into fetchable URLs (www.cnn.com ->
https://, localhost:3000 -> http://); file paths and schemes pass through
to the renderer's normalizer.
Brooklyn Nicholson