When context-compression rotation fires mid-turn, the current user
message was persisted twice into the child session. Root cause: dedup
used id()-seeded sets of copies instead of markers on the live objects.
Replace with _DB_PERSISTED_MARKER-based dedup as the sole authority:
- _ensure_compressed_has_user_turn returns CompressedUserTurnOutcome
- After publish_compression_child succeeds, stamp the live anchor-source
row (not a drifted index) with _DB_PERSISTED_MARKER
- _sync_persisted_markers mirrors stamps from result to live lists by
scoped identity (handles direct-path, adoption divergence, _session_messages)
- Remove _flushed_db_message_ids from rotation commit path (markers replace it)
- Unconditional (loud) imports — no silent fallback
Salvage of #94996 by @fedosis, rebased on top of #95433 (stall-fallback,
already merged). Both conversation_compression.py and run_agent.py are
built from origin/main + #94996's diff applied on top, preserving the
force_terminal refactor and _publish_new_fence from #95433.
Credit: @fedosis original PR #94996.
The timeout validation (isinstance(raw, (int, float)) and not
isinstance(raw, bool) and raw > 0 → float(raw)) was duplicated
between auxiliary_client.py:_fallback_entry_timeout and
conversation_compression.py:resolve_compression_fallback_route.
Extracted into _coerce_positive_timeout to prevent drift if the
config schema evolves.
Review follow-up for #95433. When the host's fence factory is absent or
raises, the retry runs on a private CompressionCommitFence() that
hard-interrupt admission never reads — /stop would serialize against the
aborted attempt's fence instead of the retry's commit boundary. Promote
the factory-failure swallow from debug to warning and warn when the retry
has no published fence, so the control-plane degradation is visible rather
than silent.
Also documents the pin's coverage (single _generate_summary call; the
lean-mode chunk digests are a separate unpinned call path).
A stalled compression summary never raises, so the auxiliary client's
exception-path fallback is unreachable from it. When the progress-aware
timeout aborts a stalled worker, re-run the summary once pinned to the
first auxiliary.compression.fallback_chain entry before degrading to
continue-without-compression.
The pin is a single-use ContextVar consumed by the context compressor's
summary call, so it cannot leak into the detached stalled worker or the
compressor's own main-model retry. A fresh fence is minted through the
host factory so a /stop during the retry still admits against the live
commit boundary.
Clicking a bot row moved the layout interaction tracker to the sidebar
group, so $focusedStoredSessionId fell back to the primary selection —
which is null in Bot Mode, because bot chats open as tiles and never set
$selectedStoredSessionId. The Bots plugin reads that null 'focused'
edge as 'the chat lost the center', releases its open claim, and the
Bots home re-asserts over the still-visible chat: the UI jumps to the
list instead of staying in the chat.
$focusedStoredSessionId now answers from the main zone's active tile in
Bot Mode before falling back to the selection, so a chrome-sidebar
click no longer fabricates a null edge; a genuinely closed chat (no
tile in main) still surfaces null and the home returns as before.
Regression tests cover the sidebar-click case (red before the fix),
plus guards for the closed-chat and sessions-mode derivations.
The write-durability contract test (test_repair_path_has_no_bare_connects)
enforces that every repair-path connection carries the macOS write
barriers; the restore rewrites the file header, so it belongs under the
same rule.
apply_durability_barriers() is the guest-connection entry point for
secondary state.db users (async delegation ledger) that must not run
journal-mode setup. database.synchronous (#90892) rides on the
journal-mode/pragma paths guests now skip, so apply it here directly —
otherwise guest connections silently run at the compile-time default.
Follow-up to the #93012 salvage.
Review feedback on #89681: the restore issued the switch pragma
directly via _set_journal_mode_no_wait, which bypassed the
vulnerable-SQLite WAL-reset gate — on the reporter's own runtime
(SQLite 3.50.4) it re-enabled WAL on the one file that had just
demonstrated it can corrupt, exactly what the gate exists to prevent
(a rebuilt file is a new database). It also skipped the WAL companions
(size limit, checkpoint barrier, synchronous=FULL) and used the
leave-WAL helper for an enter-WAL switch.
The restore now calls apply_wal_with_fallback, inheriting the gate,
the macOS-NFS silent-refusal handling and the companions from the
front door, and the pre-surgery mode is probed (best-effort; a
malformed file may refuse) and recorded in the report so the
before/after WARNING only fires when the comparison is honest.
Corruption can drop the WAL bit from the database header, and every
repair strategy rebuilds or rewrites the file in place — so a repaired
store comes back in the default journal mode (delete). The WAL-reset
gate at open time never sees the flip because it happens inside the
repair path, not at open (the open-time flip #89393 warns about is a
different door), leaving the operator no signal that a WAL store moved
to DELETE (#89674).
After a successful repair, re-apply the canonical database.journal_mode
through _set_journal_mode_no_wait (concurrent openers abort the flip
instead of sneaking it between transactions) and log a WARNING naming
the old and restored modes. Best-effort: a refused restore is logged,
never raised — the repair itself already succeeded. Probing the damaged
file for a pre-repair mode is deliberately not trusted: the corruption
itself is what drops the WAL bit, so the configured setting is the only
reliable target.
Clicking the Cronjobs tile shifts focus onto the tile itself, momentarily
dropping bot-chat workspace ownership — syncRoutinesPane then unregistered
the pane out from under the user's own click, with no way back. Keep the
tile while Bot Mode is on screen and the tile is the focused surface;
leaving Bot Mode still unregisters as designed. Live-verified.
Hiding the Sessions/Bots strip, or tapping the header of a lone docked
tile (Cronjobs and any plugin pane beside the workspace), left no mouse
path back: the restore menu lived on chrome the gesture just unmounted,
and a row-collapsed rail could size to 0px.
Treat hide-only chrome as stranded so `never` cannot hide those chips.
Stop collapsing on header tap (chevron only). Size a minimized zone to
MINIMIZED_TRACK and keep the horizontal strip when two or more tabs
remain.
job.get("schedule", {}).get("kind") crashes with AttributeError when
schedule is present but explicitly None (disk corruption edge case).
Use (job.get("schedule") or {}).get("kind") instead, which safely
returns False for None. This pattern is already used at other sites
in the file (e.g. cron/scheduler.py line 170).
is_terminal_job() treats state=error identically to state=completed at
every one of its 6 call sites (all added together in c3a63a16f1, "refuse
to run terminal jobs"). That conflates two very different situations:
* state=completed: a one-shot that genuinely has no more occurrences,
ever. Correctly terminal.
* state=error: set ONLY on a cron/interval job when compute_next_run()
fails to produce a next occurrence (e.g. the croniter package is
missing at runtime). _mark_job_run_locked's own comment is explicit:
"Recurring jobs must NEVER be silently disabled" (issue #16265) — the
job is left enabled=True specifically so it keeps being a live,
recoverable job once the underlying issue resolves.
Because is_terminal_job() lumps both together, a recurring job that ever
reaches state=error is wedged forever, with every recovery path refusing
it:
* _get_due_jobs_locked()'s own next_run_at self-heal (a few lines below
its own is_terminal_job() check) never runs, because the check itself
skips the job first.
* resume_job() -> update_job() raises "Cannot activate terminal cron job
... use cron resume --run-now or --at."
* rearm_oneshot() (the suggested alternative in that exact error message)
itself raises "Cannot re-arm recurring jobs: re-arm is one-shot-only."
* advance_next_runs() and _claim_job_for_fire_locked() — the pre-advance
and claim steps the scheduler's own dispatch loop calls immediately
after get_due_jobs() for anything that DOES make it into the due list —
both also refuse the job, so even a manually-recovered next_run_at
would fail to actually fire.
* pause_job() (itself just an update_job() call) can't even pause a
broken recurring job through the normal path.
The only way out was deleting the job and recreating it.
Fix: _is_recoverable_error_job() identifies this specific case (state ==
"error" and schedule kind in {"cron", "interval"} — the only shape
state=error ever takes) and is excluded from the is_terminal_job() gate
at update_job() (both checks), advance_next_runs(),
_claim_job_for_fire_locked(), and _get_due_jobs_locked(). trigger_job()
is left untouched: its own error message already points users at "cron
resume", which this fix makes work correctly.
Empirically verified end-to-end against the real module before writing
the fix: create a recurring job, force state=error via
_mark_job_run_locked() with compute_next_run() mocked to return None
(the exact croniter-missing scenario), then confirm resume_job() raises
ValueError, rearm_oneshot() raises ValueError, and get_due_jobs() never
recovers next_run_at. Verified after the fix: all three succeed/recover,
and claim_job_for_fire()/advance_next_runs() correctly stop refusing the
job while still correctly refusing a genuinely state=completed one-shot
through every one of those same paths.
New regression tests (tests/cron/test_terminal_job_rearm.py,
TestRecurringJobStuckInErrorStateIsRecoverable, 6 tests) cover the
due-scan self-heal, resume_job, claim_job_for_fire, advance_next_runs,
and pause_job recovery paths, plus a control confirming a genuinely
completed one-shot stays blocked on every one of the same paths.
Mutation-verified: reverting the fix reproduces exactly 5 failures (all
but the completed-oneshot control, which was never broken).
Adds contributor email→username mappings via the new
contributors/emails/ system (one file per email) for two
compression contributors whose salvage PRs need attribution CI.
* feat(tools): session-persistent kernels for execute_code (kernel_mode: session)
execute_code spawns a fresh Python process per call, so every multi-step
data task re-loads its inputs: a CSV parsed in call one is gone by call
two, and scripts route state through temp files to survive. Hermes
already rewards programmatic tool calling (execute_code-only turns
refund the iteration budget), which makes the missing half — state that
survives between calls — the bottleneck.
Add opt-in `code_execution.kernel_mode: session`: one persistent kernel
per (task, mode, interpreter, cwd, tool-set). Variables, imports, and
loaded data persist across calls; `reset=true` discards state on demand.
The default `per-call` keeps today's behavior byte-for-byte.
Safety posture is unchanged by design: the child env comes from the same
builder as the per-call path (extracted, not duplicated, so the secret
scrubbing / PYTHONPATH hygiene cannot drift), the RPC server is the same
`_rpc_server_loop` with the same token and a per-cell tool budget, and
output passes the same ANSI strip + secret redaction. A timed-out or
interrupted cell kills the whole kernel tree and the next call respawns
— a wedged kernel can never hang the agent. The kernel env is frozen at
spawn; the schema and config comment say so.
Wire protocol: NDJSON requests on the kernel's stdin; responses framed
on stdout behind a per-kernel random sentinel, with unframed bytes
(fd-level output from user-spawned subprocesses) attributed to the
serialized current cell. The generated RPC client reconnects once when
HERMES_RPC_PERSISTENT=1, because a kernel legitimately outlives the RPC
server's 300s idle window between cells.
Tested on macOS 15 (Apple Silicon), Python 3.11: 13 new tests in
tests/tools/test_code_kernel.py (persistence, reset, error-keeps-kernel,
timeout-kills-kernel, sys.exit ends kernel, subprocess fd passthrough,
schema surface, mode fallback) plus the existing
test_code_execution.py / test_code_execution_modes.py suites (81 passed).
* fix(tools): session kernels get a stable owner, bounded lifetime, and per-cell RPC authority
Addresses the blocking review on the session-kernel design: two
authority/lifecycle boundaries were wrong.
1. Ownership and bounded lifetime. The kernel key's first component is
now the conversation's approval session key (_resolve_owner), not the
per-turn task id run_agent mints per top-level invocation — so state
genuinely survives across user turns of one conversation, and delegated
subagent sessions isolate naturally under their own keys (the task id
remains only the last-resort owner for embeds/tests with no session
context). Lifetime is bounded on four edges: kernels are disposed at the
same session boundary that clears the owner's approval/yolo state
(tools.approval.clear_session -> shutdown_kernels_for_owner), reaped
after code_execution.kernel_idle_timeout seconds idle (default 1800,
swept on every entry), capped process-wide at
code_execution.max_session_kernels live children (default 4, LRU
evicted), and still torn down by reset/death/atexit as before. The
ownership + disposal + idle-reap + cap shape deliberately carries
forward the lifecycle invariants of the earlier session-persistent
implementation in #88637 by @z80dev.
2. Per-cell RPC authority. The serving thread no longer freezes the
spawning cell's context/callbacks for the kernel's life. Each cell
installs a CellAuthority — captured on the calling thread exactly as
propagate_context_to_thread would for a per-call RPC thread — before its
request is written, and retires it on every settle path; _rpc_server_loop
gains a dispatch hook the kernel uses to route each tool call through
the CURRENT cell's context, callbacks, and task id. A call arriving with
no active cell is refused. Interpreter state persists; RPC authority
does not.
Composition with the per-script static guard (see the config note): a
persistent namespace lets cell N+1 invoke objects cell N created, which
a single-cell static scan cannot see — the runtime RPC boundary
(allow-list by name, per-cell budget, per-cell authority) is the
operative cross-cell enforcement in this mode, and the adversarial
alias test pins exactly that.
Tests (9 new): state survives across turns of one conversation;
sessions isolate; clear_session disposes the owner's kernels (and the
next turn starts fresh); the live-kernel cap LRU-evicts with evicted
children proven dead; idle kernels are reaped; a later cell's RPC runs
under that cell's approval callback; a cross-cell alias dispatches under
the CURRENT cell's authority; a settled cell's authority refuses
dispatch; each cell installs a fresh authority. 22/22 kernel tests, 81
code-execution tests, ruff clean. The 7 test-order failures in the
tools/-k-approval selection reproduce identically on the clean branch
base (pre-existing pollution, not this change).
* fix(code-kernel): delegated children get their own kernels — child contexts inherit the parent approval key, so qualify the owner with the delegation session id (live-verified leak, both directions)
---------
Co-authored-by: Teknium <127238744+teknium1@users.noreply.github.com>
Automatic Desktop ends (ws_orphan_reap, disconnect, idle, LRU, shutdown)
now drop the local runtime but keep the state.db row and durable-key
delegations when another live lease still owns the session.
Co-authored-by: metamindedu <metamind@kakao.com>
Unlimited sessions used a no-op lease, so a sibling profile backend could
not see that the same durable session was still owned. Track liveness in
the profile registry without imposing a cap, and fail closed when the
registry cannot be inspected.
Co-authored-by: metamindedu <metamind@kakao.com>
- The stale tick-socket sweep's os.kill(pid, 0) liveness probe sits inside
an explicit os.name == 'posix' gate (AF_UNIX nodes never exist on
Windows) — suppress with the standard inline marker.
- contributors/emails/: rodrigo.smscom@gmail.com -> rodrigogs (author of
the salvaged #92315 commits), unblocking check-attribution.
Rebase onto today's main (#94775 salvage merged): launchd_restart's drain
now goes through _graceful_restart_via_sigusr1 before any exit-wait. The
two composed witness tests feed the REAL launchd_restart os.getpid(), so
the unmocked helper delivered an actual SIGUSR1 to the pytest process
(rc=158, killed at test 18). Mock it (and _wait_for_launchd_service_pid)
in _launchd_harness + the inline harness, and accept either drain-event
shape instead of pinning the pre-#94775 ("drain", 180.0) tuple.
Addresses the review on #92315:
- Windows behavior made explicit: AF_UNIX event-loop support doesn't exist
there, so the witness is permanently absent, the payload records
loop_tick_socket=False, and stale-file probes classify UNKNOWN, never
WEDGED — deliberate fail-safe (graceful drain remains the backstop).
WSL2, the #90502 incident environment, is Linux and arms normally.
- New test asserts the default tick_timeout/tick_strikes/tick_gap_s math
stays inside the documented probe budget so retuning can't silently
blow past the 10s subprocess query tier.
Ported from #95808 (@rtcopenclawgh, closed as duplicate of this PR):
once shutdown starts loading the loop, a heartbeat task that keeps
refreshing state/gateway.heartbeat can make a draining gateway look
healthy to external probes. Cancel it alongside the watchdog and floor
timer.
The other additive piece in #95808 — passing a confirm_s confirmation
window at the update_cmd.py probe call sites — is not needed here: this
PR's probe_gateway_loop_liveness already builds the sustained window in
(tick_strikes=3 consecutive socket misses), so every caller gets it
without a new parameter.
Co-authored-by: rtcopenclawgh <rafael@amora.com.br>
/simplify-code follow-ups on the 90502 salvage:
- _probe_loop_tick_socket_sustained: the two 'result is None' arms were
byte-identical — saw_node was effectively write-only. Collapsed to one
arm with one honest comment.
- loop_heartbeat_forever: sweep sibling gateway.loop-tick.*.sock nodes
from dead PIDs at arm time (POSIX-only liveness probe; Windows never
creates AF_UNIX nodes) so state/ does not accumulate nodes across
os._exit(75)/SIGKILL restarts. The reviewer's EADDRINUSE re-bind claim
was DISPROVED for this call site — asyncio's create_unix_server
os.remove()s an existing node before binding — but the contract is now
pinned by test_producer_rebinds_over_stale_socket_node (a live
producer arms and answers over a dead process's leftover node).
- test tmp_path fixture: yield + rmtree so the short-path mkdtemp no
longer leaks a directory per test run.
The witness tests bind real UNIX sockets under HERMES_HOME; pytest's
default tmp_path on macOS exceeds the ~104-byte sockaddr_un limit and
bind() raises 'AF_UNIX path too long' (6 failures locally, invisible on
ubuntu CI). Module-local tmp_path override uses a short mkdtemp.
The two-witness contract from the first review round still granted
destructive authority on ONE silent 1s socket probe: stale heartbeat +
armed tick socket + a single miss returned WEDGED immediately, and the
#86860 consumers take the bounded SIGTERM/SIGKILL path on that verdict.
A short transient synchronous stall (reconnect storm, heavy synchronous
callback, scheduler delay) can outlast one recv timeout, so a lone miss
is exactly the false-wedge class this change exists to prevent.
WEDGED now requires the loop to stay silent across a sustained window:
tick_strikes consecutive misses (default 3, tick_gap_s apart). Any
answer inside the window proves the loop is dispatching and returns
ALIVE; a single miss returns UNKNOWN and keeps the graceful drain path
(which also preserves #86684's cron drain floor). A witness that
vanishes mid-window is ambiguity, never a wedge.
New regression coverage:
- unit: single silent probe recovers to ALIVE; sustained silence is
required for WEDGED; vanishing witness stays UNKNOWN.
- composed (real producer + consumer): heartbeat write stalled while
the loop is frozen for longer than one tick timeout but shorter than
the wedge window -> probe is ALIVE and launchd_restart drains, never
escalates; loop frozen for longer than the window -> WEDGED.
The default probe window is ~3.4s worst case, still far inside the 10s
subprocess query tier.
The off-loop heartbeat write broke the producer->consumer invariant #86860
depends on: file freshness no longer equals loop schedulability, yet the
probe still classified a stale file as WEDGED — and WEDGED is destructive
authority (SIGTERM -> SIGKILL, bypassing the #86684 cron drain floor). The
measured motivating stall (112.6s max) exceeds the 90s stale budget, so a
healthy loop blocked inside the watchdog's own write could be killed, and
executor saturation produces the same false positive. The inverse edge
also existed: an off-loop write landing after the loop froze refreshes the
file mtime, manufacturing a false-fresh liveness proof.
The gateway loop now also arms a loop-scheduling witness: a UNIX socket
(state/gateway.loop-tick.<pid>.sock) answered by the loop itself via
await asyncio.start_unix_server — socket-buffer writes, no fsync, no disk
I/O, so it keeps working on the filesystem that stalls the heartbeat
write. The heartbeat payload records whether the witness is armed
(loop_tick_socket).
The classifier is now two-witness:
- socket answers -> ALIVE (file age irrelevant: a stalled write
or saturated executor can no longer produce a wedge verdict)
- file fresh, socket silent -> UNKNOWN (a late off-loop write can no
longer manufacture a liveness proof)
- file stale, socket silent, producer armed -> WEDGED (both witnesses
agree the loop stopped scheduling)
- legacy payload (no flag) -> unchanged single-witness contract: the
legacy producer wrote on-loop, so staleness is still proof
- any conflict/ambiguity -> UNKNOWN, never escalate
Tests are a producer->consumer composition: a real heartbeat loop with a
stalled write probes ALIVE while the file is past the stale budget, and
launchd_restart fed by the real probe drains instead of escalating; a
silent socket with a fresh file denies ALIVE; WEDGED requires the armed
socket to agree; a bind-failed producer disables stale escalation; legacy
payloads keep the old contract; a source-inspection test pins that the
witness is awaited on the loop. Mutation-checked: reverting either source
file fails the new tests. 45 tests pass across the watchdog suites; ruff
clean.
`loop_heartbeat_forever` wrote the heartbeat inline on the gateway loop. That
write ends in `atomic_json_write` -> `os.fsync`, and on a stalling filesystem the
fsync blocks whichever thread runs it — which was the loop the liveness watchdog
exists to monitor. So the watchdog timed out its probe
(DEFAULT_LOOP_WATCHDOG_TIMEOUT_S = 10s, MAX_STRIKES = 3, a ~90-120s budget) and
took the hard exit, for a loop that was unresponsive because it was blocked
inside the watchdog's own liveness write.
Measured on the install that prompted this: a WSL2 VHDX under io pressure
(/proc/pressure/io full avg300 = 7.60) stalled a trivial stat-and-fsync probe at
p99 31s and max 112s — longer than the entire watchdog budget. Two of that day's
three gateway restarts carry byte-identical stack dumps parked in the heartbeat
writer.
The write now goes to a thread. Awaited, not fire-and-forget, and that distinction
is the whole design: the docstring promises that a frozen loop lets the file age,
because that staleness is how an external supervisor notices. The loop still
initiates and awaits the write, so a wedged loop still stops refreshing the file —
while a blocked fsync no longer stops the loop from answering the probe. One write
in flight at a time, so a 112s stall cannot queue a thread per interval behind it.
Scope: the timeout and strike defaults are untouched. Raising them would only
delay the same kill, and picking a budget above this box's p99 is a deployment
decision, not a fix.
2 tests. The behavioural one patches a slow write and asserts the loop still
completes ~15 ticks while it blocks; it is bounded by a fixed sleep rather than an
Event handshake so a regression fails on the tick count instead of hanging. The
second pins that the write stays awaited, since fire-and-forget would pass the
first test while destroying the staleness signal.
Verified by mutation: reverting only gateway/shutdown_watchdog.py fails both new
tests and leaves the 5 existing ones green. 15 passed across
test_loop_liveness_watchdog / test_shutdown_watchdog /
test_systemd_watchdog_lifecycle / test_watchdog_review_76354.
A live sibling serve sharing state.db is no longer treated as a dead process by the startup orphan sweep.
Covers the sweep half of #94895. The launchd Errno 48 KeepAlive loop is not addressed here.
Credit: @Finn763
Unquoted 2070 as a providers: key or custom_providers name must list, mark
current, activate, and delete instead of 500/404.
Co-authored-by: xxxigm <tuancanhnguyen706@gmail.com>
PyYAML loads unquoted names like provider: 2070 as int. GET /api/model/options
then called .lower() on the providers dict key and 500ed, and activate/delete
looked up "2070" and missed. Stringify identity fields so Desktop can assign
and remove those endpoints.
Co-authored-by: xxxigm <tuancanhnguyen706@gmail.com>
Mistral ignores response_format=text and returns the full transcription
object. Desktop was dumping that JSON into the composer; pull .text out
so dictation shows the spoken words instead.
Both from the simplify pass: the comment kept only the ownership-relevant
rationale (incl. the no-double-bump note); the test's _ReadyAdapter was a
verbatim delegate around threading.Event — the exercised paths only call
is_set/clear/set, so the bare Event is behaviorally identical.
Widen the contributor's pre-call reconnect signal to the sibling site:
when the stdio subprocess dies mid-RPC the watcher race fast-fails, but
nothing cleared server.session, so the server stayed dead until the idle
keepalive probe noticed. Signal the reconnect there as well.
Also drop the explicit _bump_server_error at the pre-call gate: the
returned error payload already flows through the handler's JSON parse,
which bumps the breaker once — the explicit bump would double-count.
Two regression tests pin both sites (reconnect signaled exactly once,
no RPC attempted on a dead transport, single breaker bump).
_stdio_children_dead() returned True ('all children dead') when a child
process was ALIVE — the liveness predicate was inverted:
for pid in pids:
if not psutil.pid_exists(pid):
continue # dead — skip
return True # BUG: an ALIVE child reported as 'all dead'
Consequence: every tools/call on a stdio MCP server with a healthy
subprocess failed instantly (~0.01-0.3s) with
'MCP stdio subprocess has exited; failing the call fast' (#81995
fast-fail path), while hermes mcp test kept passing (it never reaches
tools/call). Servers appeared dead regardless of restarts.
Fix: return False as soon as one tracked child is alive; True only when
every child has exited:
for pid in pids:
if psutil.pid_exists(pid):
return False # at least one child alive
return True
Also: on a genuinely-dead stdio (session object still present), signal
reconnect instead of a bare fast-fail TimeoutError, so the manager
respawns the subprocess instead of stranding the call slot.
Verified: alive child -> False, all exited -> True, no tracked pids ->
False (unknown, don't fail fast).
kshitij