diff --git a/.agents/skills/lib_py/agents/adapters/claude.py b/.agents/skills/lib_py/agents/adapters/claude.py
index a093a46..2510761 100644
--- a/.agents/skills/lib_py/agents/adapters/claude.py
+++ b/.agents/skills/lib_py/agents/adapters/claude.py
@@ -1,6 +1,6 @@
 import os, re, json, glob, math, stat, time, shutil, calendar, subprocess
 from typing import Optional, Any
-from lib_py.agents.base import BaseAgentAdapter, DiscoveryContext, conversation_in_use, scan_names, _plausible_id
+from lib_py.agents.base import BaseAgentAdapter, DiscoveryContext, conversation_in_use, scan_names
 from lib_py.verify_session import workspace_key
 
 
@@ -306,20 +306,15 @@ class ClaudeAgentAdapter(BaseAgentAdapter):
         never listed."""
         # Checked before any path is built: whole directories named by the id
         # are removed, so "", "." or ".." would reach file-history/ itself,
-        # and "memory" the auto memory. An id that is not a uuid keeps the
-        # pre-#31 reach: the `<id>.jsonl` file alone.
-        if not _plausible_id(uuid):
+        # and "memory" the auto memory. Only a uuid names a session.
+        uuid = _canonical(uuid)
+        if not uuid:
             return []
-        canon = _canonical(uuid)
         cfg = _config_dir(ctx)
         found = []
         for pdir in _projects_dirs(ctx):
-            base = os.path.join(pdir, ctx.ws_key, canon or uuid)
-            found += [(pdir, p) for p in ((base + ".jsonl", base) if canon else (base + ".jsonl",))
-                      if os.path.lexists(p)]
-        if not canon:
-            return found
-        uuid = canon
+            base = os.path.join(pdir, ctx.ws_key, uuid)
+            found += [(pdir, p) for p in (base + ".jsonl", base) if os.path.lexists(p)]
         found += [(cfg, p) for p in (os.path.join(cfg, "file-history", uuid),
                                      os.path.join(cfg, "session-env", uuid)) if os.path.lexists(p)]
         job = self._owned_job(uuid, ctx)
@@ -370,7 +365,9 @@ class ClaudeAgentAdapter(BaseAgentAdapter):
         # shows up in residual_artifacts instead.
         # Ownership evidence (a job's state.json, a session file) is removed
         # only after what it vouches for, so a retry can still find the rest.
-        uuid = _canonical(uuid) or uuid
+        uuid = _canonical(uuid)
+        if not uuid:
+            return []
         purged = []
         job = self._owned_job(uuid, ctx)
         for path in self._owned_paths(uuid, ctx):
@@ -390,9 +387,9 @@ class ClaudeAgentAdapter(BaseAgentAdapter):
         roots (two levels), plus the content-matched jobs dir and session
         files with their (masked) key files. projects is not walked deeper;
         it can be very large."""
-        if not _canonical(uuid):
-            return sorted(p for _, p in self._candidates(uuid, ctx))
         uuid = _canonical(uuid)
+        if not uuid:
+            return []
         cfg = _config_dir(ctx)
         pdirs = _projects_dirs(ctx)
         found = set(scan_names(cfg, uuid, skip=pdirs))
diff --git a/tests/test_issue31_purge_residual.py b/tests/test_issue31_purge_residual.py
index b48590f..bb21e4d 100644
--- a/tests/test_issue31_purge_residual.py
+++ b/tests/test_issue31_purge_residual.py
@@ -420,27 +420,29 @@ def test_claude_roots_may_be_links(home, tmp_path, monkeypatch, conv):
     assert adapter.residual_artifacts(conv, ctx) == []
 
 
-def test_a_non_uuid_id_takes_only_its_transcript_file(home, tmp_path):
-    """The pre-#31 reach, kept for ids that are not uuids (test_a4 purges
-    "uuid-c"): the `<id>.jsonl` file, never a directory of that name."""
+@pytest.mark.parametrize("name", ["uuid-c", "memory", "notes"])
+def test_a_non_uuid_id_reaches_nothing(home, tmp_path, name):
+    """Only a uuid names a claude session: no path is built for any other id,
+    not even the `<id>.jsonl` the adapter took before #31."""
     ws = tmp_path / "ws"
     ws.mkdir()
     proj = home / ".claude" / "projects" / workspace_key(str(ws))
     proj.mkdir()
-    jsonl = proj / "uuid-c.jsonl"
-    jsonl.write_text("{}\n")
-    kept = [proj / "uuid-c" / "a", home / ".claude" / "file-history" / "uuid-c" / "b"]
-    for p in kept:
+    jsonl = proj / f"{name}.jsonl"
+    jsonl.write_text(json.dumps({"sessionId": name, "cwd": os.path.realpath(str(ws))}) + "\n")
+    kept = [jsonl, proj / name / "a", home / ".claude" / "file-history" / name / "b"]
+    for p in kept[1:]:
         p.parent.mkdir(parents=True)
         p.write_text("x")
     adapter = get_adapter("claude")
     ctx = _ctx(ws, home)
 
-    assert adapter.has_artifacts("uuid-c", ctx) is True
-    assert adapter.residual_artifacts("uuid-c", ctx) == [str(jsonl)]
-    assert adapter.purge_artifacts("uuid-c", ctx) == [str(jsonl)]
-    assert not jsonl.exists() and all(p.exists() for p in kept)
-    assert adapter.residual_artifacts("uuid-c", ctx) == []
+    assert adapter.has_artifacts(name, ctx) is False
+    assert adapter.residual_artifacts(name, ctx) == []
+    assert adapter.purge_artifacts(name, ctx) == []
+    res = _agents_cli(["purge", "claude", name, str(ws)], ws)
+    assert json.loads(res.stdout)["purged"] == [], res.stdout + res.stderr
+    assert all(p.exists() for p in kept)
 
 
 def test_purge_cli_resolves_claude_from_leftovers_only(home, tmp_path, conv):