fix(conversation_store,admin,cli): keep session when file lags db, sort pty by recency

src/beaver_gateway/agents/claude.py

@@ -171,6 +171,16 @@ class ClaudeCodeOptions(BaseModel):
     terminal assistant has been seen. Bound on extra latency when
     ``wait_for_turn_duration=True``."""
 
+    idle_session_ttl: float = 1800.0
+    """Seconds a pooled claude session may sit unused before it is
+    terminated. The backend pools live PTYs by conversation-history
+    fingerprint; when a conversation forks, the session behind the old
+    fingerprint becomes unreachable but stays resident — one live
+    ``claude`` (hundreds of MB) each. 30 minutes keeps an active chat
+    warm across a coffee break while bounding what a fork storm can
+    strand. There is no count cap: concurrent conversations should all
+    stay warm. ``0`` disables reaping."""
+
 
 class ClaudeAgent(BaseAgent):
     """Agent backed by ``claude-code-api``.

src/beaver_gateway/backends/claude_code.py

@@ -199,6 +199,7 @@ def _build_backend_options(
         startup_delay=opt.startup_delay,
         file_wait_timeout=opt.file_wait_timeout,
         turn_duration_timeout=opt.turn_duration_timeout,
+        idle_session_ttl=opt.idle_session_ttl,
     )
 
 

src/beaver_gateway/cli.py

@@ -21,7 +21,9 @@ it just keeps the aggregator running for anyone who needs it.
 from __future__ import annotations
 
 import asyncio
+import contextlib
 import logging
+import signal
 from contextlib import AsyncExitStack
 from typing import TYPE_CHECKING
 
@@ -60,9 +62,33 @@ def main() -> None:
     logging.basicConfig(
         level=logging.INFO, format="%(asctime)s %(levelname)s %(name)s: %(message)s"
     )
+    _install_sigterm_handler()
     asyncio.run(_async_main(), loop_factory=uvloop.new_event_loop)
 
 
+def _install_sigterm_handler() -> None:
+    """Turn SIGTERM into a normal interpreter exit.
+
+    Python's default SIGTERM disposition kills the process outright, so
+    neither ``AsyncExitStack`` unwinding nor ``atexit`` hooks run. That
+    matters because every ``claude`` we spawn lives in its own session
+    (ptyprocess calls ``setsid``), which makes it immune to the signal
+    that took us down — a hard SIGTERM leaves one orphaned CLI per live
+    session, each holding hundreds of MB. Raising ``KeyboardInterrupt``
+    instead routes ``docker stop`` / ``systemctl stop`` through the same
+    shutdown path as Ctrl-C, which does reap them.
+
+    Only installed when we own the main thread's signal handlers; under
+    an embedding host that isn't ours to take.
+    """
+
+    def _raise_interrupt(_signum: int, _frame: object) -> None:
+        raise KeyboardInterrupt
+
+    with contextlib.suppress(ValueError, OSError):
+        signal.signal(signal.SIGTERM, _raise_interrupt)
+
+
 async def _async_main() -> None:
     # Populate ``os.environ`` from ``.env`` before anything else so the
     # user's ``config.py`` can read its own secrets via ``os.environ[...]``

src/beaver_gateway/core/conversation_store.py

@@ -398,6 +398,15 @@ def diff_and_fork(
     spliced_groups, divergence = _walk_prefix(prior_incoming, stored_groups)
 
     if divergence is None and len(prior_incoming) < len(stored_groups):
+        if _file_lags_store(stored_groups, len(prior_incoming), new_user_turn):
+            # Not a deletion — the file simply never received turns we
+            # already ran. Adopt the stored tail verbatim so history stays
+            # structured and its fingerprint still matches the live
+            # session's. See ``_file_lags_store`` for why this matters.
+            spliced_groups.extend(
+                list(g.messages) for g in stored_groups[len(prior_incoming) :]
+            )
+        else:
             # Incoming truncated stored (user deleted some past turns).
             # Truncate stored to match.
             divergence = len(prior_incoming)
@@ -415,6 +424,38 @@ def diff_and_fork(
     )
 
 
+def _file_lags_store(
+    stored_groups: list[_StoredDisplayTurn], prior_len: int, new_user_turn: ParsedTurn
+) -> bool:
+    """Is the shorter incoming file a stale view rather than a deletion?
+
+    A file with fewer display turns than the DB has two possible causes,
+    and they need opposite handling:
+
+    * the user deleted trailing turns — we should truncate to match;
+    * the turn ran, was persisted, but its reply never made it back into
+      the ``.md`` (the render lost a race with the user's next prompt, or
+      the reply rendered to nothing visible). The file is simply behind.
+
+    The tell is the prompt the user is submitting right now: if the DB
+    already holds it at exactly the position the file stops at, this is a
+    re-submission of a turn we've already run, not a deletion. Nobody
+    deletes a turn and immediately retypes it verbatim.
+
+    Getting this wrong is expensive and self-sustaining. Forking here
+    flattens every post-divergence turn into plain text (losing tool_use /
+    tool_result structure), persists that flattened history, and changes
+    the conversation fingerprint — so the backend's session pool misses,
+    spawns a fresh ``claude``, reseeds it from a multi-MB JSONL, and
+    strands the previous process. The file still lags afterwards, so the
+    next turn does it again.
+    """
+    if prior_len >= len(stored_groups):
+        return False
+    candidate = stored_groups[prior_len]
+    return candidate.role == "user" and candidate.spoken_text == new_user_turn.text
+
+
 def _walk_prefix(
     prior_incoming: list[ParsedTurn], stored_groups: list[_StoredDisplayTurn]
 ) -> tuple[list[list[dict[str, Any]]], int | None]:

src/beaver_gateway/frontends/admin/frontend.py

@@ -567,13 +567,19 @@ def _collect_pty_sessions(runtime: GatewayRuntime) -> list[dict[str, Any]]:
     (currently only ``ClaudeCodeBackendAdapter``). Other backend types
     are quietly skipped — the admin terminal viewer only makes sense for
     PTY-backed agents.
+
+    Sorted most-recently-used first. The underlying mapping is keyed by
+    conversation fingerprint and reshuffled on every pool hit, so its
+    iteration order carries no meaning a human could act on.
     """
+    now = time.time()
     out: list[dict[str, Any]] = []
     for agent_name, backend in runtime.backends.items():
         live = getattr(backend, "live_sessions", None)
         if not isinstance(live, dict):
             continue
         for session_id, pty in live.items():
+            last_used = getattr(pty, "last_activity_at", None) or now
             out.append(
                 {
                     "agent": agent_name,
@@ -582,11 +588,28 @@ def _collect_pty_sessions(runtime: GatewayRuntime) -> list[dict[str, Any]]:
                     "buffer_size": len(pty.captured_output())
                     if hasattr(pty, "captured_output")
                     else 0,
+                    "last_used": last_used,
+                    "idle": _humanize_duration(now - last_used),
+                    "age": _humanize_duration(
+                        now - (getattr(pty, "created_at", None) or now)
+                    ),
                 }
             )
+    out.sort(key=lambda s: s["last_used"], reverse=True)
     return out
 
 
+def _humanize_duration(seconds: float) -> str:
+    """Render a duration as the coarsest unit that still reads precisely."""
+    secs = max(0, int(seconds))
+    if secs < 60:
+        return f"{secs}s"
+    if secs < 3600:
+        return f"{secs // 60}m {secs % 60}s"
+    hours, rem = divmod(secs, 3600)
+    return f"{hours}h {rem // 60}m"
+
+
 def _find_pty(runtime: GatewayRuntime, session_id: str) -> Any:
     """Locate a live PTY by its claude session_id, across all backends."""
     for backend in runtime.backends.values():

src/beaver_gateway/frontends/admin/templates/pty_list.html

@@ -4,8 +4,9 @@
 {% block content %}
 <h2>Live PTY sessions</h2>
 <p class="muted">
-  Each row is a running <code>claude</code> subprocess. Open one to see what's
-  currently rendered on its TUI and (if needed) type into it directly.
+  Each row is a running <code>claude</code> subprocess, most recently used first.
+  Open one to see what's currently rendered on its TUI and (if needed) type into
+  it directly. Sessions idle past the agent's TTL are terminated automatically.
 </p>
 
 {% if sessions %}
@@ -15,6 +16,8 @@
       <tr>
         <th>Session ID</th>
         <th>Agent</th>
+        <th>Idle</th>
+        <th>Age</th>
         <th>PID</th>
         <th>Buffer</th>
         <th></th>
@@ -25,6 +28,8 @@
       <tr>
         <td><code>{{ s.session_id }}</code></td>
         <td>{{ s.agent }}</td>
+        <td>{{ s.idle }}</td>
+        <td class="muted">{{ s.age }}</td>
         <td><span class="pill">{{ s.pid or "?" }}</span></td>
         <td>{{ s.buffer_size }} bytes</td>
         <td>

uv.lock

@@ -287,7 +287,7 @@ local = [
     { name = "raycast-api", version = "0.1.0", source = { editable = "../raycast-api" } },
 ]
 prod = [
-    { name = "claude-code-api", version = "0.1.0", source = { git = "https://git.kotikot.com/beaver/claude-code-api.git#4f6585b1ac16746de3724c36b5211a24181fd948" } },
+    { name = "claude-code-api", version = "0.1.0", source = { git = "https://git.kotikot.com/beaver/claude-code-api.git#89065c2f4ed8db5607ae49e236a8e398719c8072" } },
     { name = "raycast-api", version = "0.1.0", source = { git = "https://git.kotikot.com/beaver/raycast-api.git#e73894c8e435da5c0709f92f69f11bcd0dab9afe" } },
 ]
 
@@ -419,7 +419,7 @@ wheels = [
 [[package]]
 name = "claude-code-api"
 version = "0.1.0"
-source = { git = "https://git.kotikot.com/beaver/claude-code-api.git#4f6585b1ac16746de3724c36b5211a24181fd948" }
+source = { git = "https://git.kotikot.com/beaver/claude-code-api.git#89065c2f4ed8db5607ae49e236a8e398719c8072" }
 resolution-markers = [
     "python_full_version >= '3.14'",
     "python_full_version < '3.14'",