A sandbox header bought isolation by taking the document's origin away, and
measuring that cost decided against it: the reported artifact throws
SecurityError on load, and because an uncaught exception aborts the rest of
its <script>, every listener declared after that line — theme toggle, mobile
menu, model tabs — never binds. Two of the four artifacts in the reporting
user's workspace were dead pages under it, and they still looked right.
A second listener on the API's host, answering /f and nothing else, is the
same boundary without the amputation: cross-origin to /api (refused by the
Origin fence and by CORS), same-origin with itself (localStorage, cookies and
fetch all work). Its port is published into the index page; the browser half
reads it to address previews, and its absence — the keyless fixture lane — is
what makes a file row fall back to the Host opener instead of a dead tab.
fileUrl moves from IWorkspaces to ConnectionHandle: the transport owns both
the listener that serves the bytes and the port that addresses it.
Isolation is restored on the premise the review corrected: a workspace file
need not be agent-authored — a read row makes every file in a cloned
repository openable — and a same-origin active document was measured driving
/api/settings.describe to a 200 with full data. Script-capable documents go
back into an opaque origin; the preview's lost localStorage is the known cost,
and a separate serving origin is the way to retire it.
- confine(): a workspace rooted at a filesystem root has a realpath already
ending in the separator, and the doubled prefix 403'd every child.
- turnDeliverables(): reset on the turn boundary, not only at a closing
assistant, so an interrupted turn cannot spill into the next turn's row;
and recognize a mutation by render intent (diff card, or generic with
kind 'edit') so str_replace_editor's insert counts.
- 405 answers name the methods it allows.
- The e2e now cold-seeds a recorded WRITE turn, so the assembled application
covers the Produced row, its chip's served URL, and the isolation header.
- Agent Note matched to what shipped (the row is in this PR, not deferred);
ui-conversation README documents the new destination and the row; the
fixture lane's dead-tab quirk and the cold-path listing cost are recorded.
A preview lost localStorage and cookies under CSP sandbox — measurably, the
reported artifact throws SecurityError on load and its theme toggle goes
dead. The capability the sandbox denied is one the file's author, an agent
already holding this user's shell, never needed the browser for, so the
header sat behind a trust boundary it had already crossed.
Isolating a preview becomes a real question when workspace content stops
being the viewer's own; the answer then is a separate origin, not a header.
The paths come from the mutation tools' follow-along locations, not from the
closing prose, so a turn's output is listed whether or not the model named
it. Each chip opens through the same openFile the tool rows use.
Reads contribute nothing (looking at a file does not produce it), a failed
mutation contributes nothing, a file touched twice is one entry, and the row
shows six with an explicit remainder rather than burying the answer.
Serve one file at a time out of a Session's workspace under /f on the web
transport, and point the conversation's existing file-open affordance at it.
Clicking a write/edit/read row's path now opens that file in a browser tab —
including from a LAN client, where the Host's system opener is fenced to
loopback and answered nothing.
- /f/<sessionId>/<segments> in client-connection, behind the same
browser-trust fence as /api; realpath confinement, streamed reads,
GET/HEAD only, nosniff + no-store.
- Script-capable documents carry CSP sandbox: model-authored markup must not
be same-origin with /api, where events.mux is a readable GET stream.
- ApiProxy.workspaceRootOf answers where a Session's files live without
resuming an agent; the client program cannot reach the core services.
- The /f URL shape lives in dsh-host-apiproxy/api so both ends share one
encoding (client bundles may not value-import another plugin).
The timeout promise's executor runs synchronously while the race is
constructed, so the timer is always assigned; the undefined check was a
dead branch the per-file coverage gate rejected.
The fork button on a stopped assistant message was inert. Frozen
interrupted nodes carry a flow-ordering seq of turnEnd.seq - 0.9, and
session.fork takes a non-negative integer on the wire, so every such
request was rejected as invalid-params before reaching the host — where
an aborted turn's logged turn/end has always made it forkable.
SessionsService.fork floors atSeq at the wire boundary. Flooring stays
inside the anchor's own turn (every turn opens with turn/start), so the
host's first-turn/end-at-or-after cut still closes on that turn.
The PTY capture does continue past the terminal-takeover bytes with the
fatal diagnostic; only the reset never follows. State that precisely in
both notes.
Document on FailLoudProcess.exit that callers treat it as the end of the
run, matching how the release path already relies on it.
Review of the previous commit found two defects in the release path, both
reproduced against the implementation:
- The timeout guarding a never-settling release was unref'ed. An
unhandledRejection listener suppresses Node's default fatal exit, so with
nothing else referenced the process reached an empty event loop and exited
0 on the very failure it was reporting. Keep the timer referenced and clear
it once the race settles.
- The handler uninstalled itself before awaiting the release. A second
concurrent rejection then became uncaught and killed the process
mid-teardown, stranding exactly the terminal state this restores. Replace
the uninstall with a latch: the first rejection is the reported one, and
later rejections (teardown's own included) fall through to the pending exit.
Add the PTY regression the fake-process tests cannot express: boot the shipped
tree over a fixture whose llm-pi-ai providers value is list-shaped, expect exit
1, and assert the captured bytes carry both the diagnostic and ESC[?2004l.
Against the pre-fix source the stream ends at ESC[?2004h ESC[>7u ESC[?u ESC[c
with no reset and the case fails, so it pins the actual bug.
Split the two-shape formatting test into one install per case; a latched
handler reports once by design.
A dsh launch whose config failed validation returned the user to a broken
shell: typing was invisible and the next command was mangled by a stray
Device Attributes reply (1;2;4cecho ...).
The Loader mounts entries concurrently, so ui-tui can already hold the
terminal (raw mode, bracketed paste, keyboard protocol, plus an in-flight
DA query) when a sibling entry rejects on its own config. installFailLoud
wrote its diagnostic and exited immediately, so nothing disposed the tree
and ProcessTerminal.stop() never ran.
Give installFailLoud an optional release teardown, awaited between the
diagnostic and the exit and bounded by FAIL_LOUD_RELEASE_TIMEOUT_MS. The
TUI launcher passes one that disposes the root context, reaching the same
shutdown() the /exit path already uses (drainInput() + ui.stop()). The
context is captured in boot()'s prepare hook because the rejection arrives
while boot() is still in flight.
Bins that pass no release keep the previous behavior exactly.