fix(reset,stop): warn before a reset purges, skip and prune stale registries, refuse a guessed purge

reset.sh without --yes says the conversations are deleted for good before it
asks; without a terminal the refusal says so too. A registry that cannot be
created is skipped, since nothing can be registered there, and the directories
the fence created are removed on exit when still empty. stop --purge-conversation
refuses a conversation the row does not record instead of deleting the folder's
newest one.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VCgu9Fa9iT7TbJUSzdq4Ff

.agents/skills/lib_py/agents/session_ids.py

@@ -154,6 +154,13 @@ def decide_stop(state: Dict[str, Any], name: str, agent: str, cwd: str,
                 "purge_uuid": "",
                 "note": f"{found} is also recorded by {others}; registry needs fixing",
             }
+        if purge and found and found != own:
+            return {
+                "captured": "",
+                "status": "purge-unrecorded",
+                "purge_uuid": "",
+                "note": f"{found} is this folder's newest conversation, not an id this row records",
+            }
         return {
             "captured": found,
             "status": "resolved" if found else "no-candidate",

.agents/skills/lib_py/reset.py

@@ -22,7 +22,7 @@ from typing import Dict, Iterator, List, Mapping, Optional, Tuple
 
 from lib_py.agents.base import AGENT_SESSION_ENV, POST_DISCOVERED
 from lib_py.agents.registry import agent_of_row, get_adapter, own_key
-from lib_py.delegation.mqtt_common import registry_lock
+from lib_py.delegation.mqtt_common import LOCK_FILENAME, registry_lock
 from lib_py.delegation.registry import RESET_MARKER, reset_marker
 from lib_py.update import jobs_dirs, open_jobs, row_server
 from lib_py.verify_session import verify_session_uuid
@@ -497,7 +497,10 @@ def fence_registries(workspace: str, state: dict, env: Mapping[str, str]) -> Ite
     fenced by another live (or undecidable) reset - registries may be shared
     between workspaces; its marker is left as it is. This workspace's own
     registries refuse every registration; another control plane's only those
-    addressed to this registry's rows. The marker copies .mam/reset-in-progress."""
+    addressed to this registry's rows. The marker copies .mam/reset-in-progress.
+    Yields ("created", path) per directory level it makes, deepest first, then
+    ("fenced", real path). A registry that cannot be created is skipped: nothing
+    can be registered there."""
     with open(os.path.join(workspace, ".mam", "reset-in-progress"), encoding="utf-8") as fh:
         base = "".join(l + "\n" for l in fh.read().splitlines() if l.split("=", 1)[0] in ("pid", "lstart", "started"))
     me = dict(l.split("=", 1) for l in base.splitlines()).get("pid", "")
@@ -505,7 +508,17 @@ def fence_registries(workspace: str, state: dict, env: Mapping[str, str]) -> Ite
     rows = state.get("herdr_sessions") or []
     sessions = ",".join("herdr:%s" % s["name"] for s in rows if s.get("name"))
     for d, addressed_only in jobs_dirs(workspace, state, env):
-        os.makedirs(d, exist_ok=True)
+        missing = []
+        p = os.path.abspath(d)
+        while not os.path.lexists(p):
+            missing.append(p)
+            p = os.path.dirname(p)
+        try:
+            os.makedirs(d, exist_ok=True)
+        except OSError:
+            continue
+        for p in missing:
+            yield "created", p
         with registry_lock(d):
             held, fields = reset_marker(d)
             if held in ("live", "unknown") and fields.get("pid") != me:
@@ -516,7 +529,21 @@ def fence_registries(workspace: str, state: dict, env: Mapping[str, str]) -> Ite
             with os.fdopen(fd, "w", encoding="utf-8") as fh:
                 fh.write(base + ("sessions=%s\n" % sessions if addressed_only else ""))
             os.replace(tmp, os.path.join(d, RESET_MARKER))
-        yield _real(d)
+        yield "fenced", _real(d)
+
+
+def prune_created(paths: List[str]) -> None:
+    """Remove the directories fence_registries created, deepest first, each only
+    while nothing but its registry lock file is left in it."""
+    for d in paths:
+        try:
+            if os.path.isfile(os.path.join(d, LOCK_FILENAME)):
+                with registry_lock(d):
+                    if os.listdir(d) == [LOCK_FILENAME]:
+                        os.unlink(os.path.join(d, LOCK_FILENAME))
+            os.rmdir(d)
+        except OSError:
+            continue
 
 
 def target_id_owned(state: dict, session_name: str) -> bool:
@@ -795,6 +822,10 @@ def main(argv: Optional[List[str]] = None) -> int:
     s = sub.add_parser("fence")
     s.add_argument("--workspace", required=True)
 
+    s = sub.add_parser("prune-created")
+    s.add_argument("--workspace", required=True)
+    s.add_argument("paths", nargs="*")
+
     s = sub.add_parser("id-owned")
     s.add_argument("--workspace", required=True)
     s.add_argument("--session", required=True)
@@ -886,8 +917,8 @@ def main(argv: Optional[List[str]] = None) -> int:
 
     if a.cmd == "fence":
         try:
-            for d in fence_registries(ws, state, os.environ):
-                print("fenced %s" % d, flush=True)
+            for kind, d in fence_registries(ws, state, os.environ):
+                print("%s %s" % (kind, d), flush=True)
         except FenceBusy as exc:
             print("refused %s" % exc)
             return 1
@@ -896,6 +927,10 @@ def main(argv: Optional[List[str]] = None) -> int:
             return 1
         return 0
 
+    if a.cmd == "prune-created":
+        prune_created(a.paths)
+        return 0
+
     if a.cmd == "id-owned":
         return 0 if target_id_owned(state, a.session) else 1