# Review 916abd41 — PR #59 second pass, Issue #31

Reviewed only the snapshot `/var/folders/q_/68sxgw3j073dgjg8wl9s08vw0000gn/T/mam-review/loop-20261017T135731Z-e93f0a/1` (`loop-20261017T135731Z-e93f0a`). Head `2a8d73825b3832376aeaf96b09548359dc3cb887`, tree `d146f1ac68bcc3485d24fb92edb87264e4d1e8cb`, base `26e2c43753169671b600d03274901dbe203988dd` is an ancestor. Versus base: 13 files, +1462/−30. Versus the first-review head `6f4f40a4adb2115d5997dffd31fb6473f05cab68`: 11 commits (`26fb1c4`..`2a8d738`), 7 files, +382/−50. `git diff --check` is clean. Snapshot porcelain is empty and the snapshot has no `.mam`. Control-plane main is still `26e2c43753169671b600d03274901dbe203988dd`, porcelain empty. No product file was edited.

Host tools: `/usr/bin/python3` 3.9.6, the control-plane venv the same 3.9.6, `/bin/bash` 3.2.57 (and `/bin/sh` is that bash). `bash -n` accepts `stop_session.sh` and `lib.sh`.

Every purge and `in-use` exercised here used a temporary `HOME`, `CLAUDE_CONFIG_DIR`, `CLAUDE_PROJECT_DIR`, `CLAUDE_CODE_TMPDIR`, and `TMPDIR`. The real `~/.claude` and `/private/tmp/claude-<uid>` were listed with read-only counts. `_session_file_live` was called on the real session files and deleted nothing.

## What this Mac already stores

`~/.claude` has real directories `file-history`, `session-env`, `sessions`, `jobs`, and `projects`. `file-history` holds 19 entries and no symlinks. `session-env` holds 21 entries and no symlinks. `sessions` holds 6 `*.json` files and 6 key files. `jobs` holds 3 directories, none of them symlinks, and 2 of those names are 8 characters. `projects` has 16 keys, none of them symlinks.

`/tmp` is a symlink to `/private/tmp`. `/tmp/claude-<uid>` and `/private/tmp/claude-<uid>` both exist, share one real path, and that directory has 7 entries. `CLAUDE_CODE_TMPDIR` was unset in this review process before the probes pointed it at a temp directory.

## lstart on this host

`ps -p <pid> -o lstart=` with `LC_ALL=C` prints five fields. With `TZ=UTC0` the string differs from the default-TZ string. `calendar.timegm` of the UTC string sits 0.367 s behind `time.time()` for a fresh `sleep`. `time.mktime` of the default-TZ string sits the same 0.367 s behind. macOS `ps` honors `TZ=UTC0`, so the UTC parse in `_session_file_live` (`claude.py:97-105`) is the process start, and a DST fold is the same instant in both readings.

On the six live session files, `_session_file_live` returned live for all six and stale for none. `lstart - startedAt/1000` is between −2.362 s and −0.771 s, so `lstart <= startedAt/1000 + 2` holds for every one of them.

A temp-home probe of the same function: a live pid with `startedAt` set to now, NaN, inf, `10**400`, a digit string, or boolean `True` is live. A dead pid is stale, including a dead pid whose `startedAt` is NaN (`ProcessLookupError` returns before the time check, `claude.py:78-81`). The same live pid with `startedAt` an hour earlier is stale.

## The three findings from the first review

Canonical uuid. `_canonical` (`claude.py:10-18`) returns the lowercase spelling only when the whole string is a uuid. `_canonical("memory")` is `None`, and an uppercase uuid comes back lowercase. On a temp config, `purge_artifacts("memory")` returned `[]`, residual was empty, `conversation_in_use("memory")` was false, and both `projects/<key>/memory/MEMORY.md` and `memory.jsonl` stayed. `purge_artifacts("....")` returned `[]`.

Linked directories. `_inside` (`claude.py:108-122`) walks `dirname(path)` with `lstat` and rejects a symlink component below the root, then requires the resolved parent to sit under the resolved root. A temp `<tmp-root>/<key>` symlink to an outside directory stayed a symlink, the outside `keep.txt` stayed, that linked path was listed by `residual_artifacts`, and the purged list had no outside path. The real `file-history/<uuid>` and the jsonl for that same id were removed once the holder was gone. A `file-history/<uuid>` symlink was unlinked and its target `secret.txt` stayed. A symlink child inside a real owned `<uuid>/` directory was removed with that directory, and the target file stayed.

Non-finite `startedAt`. The probe above: NaN, inf, and an int too large for float are live while the pid is alive, and a dead pid is stale. That is `claude.py:84-95`.

Uppercase spelling while a session file names a live pid: `conversation_in_use` of the uppercase id was true. `python -m lib_py.agents purge claude <UPPER> <ws>` exited 4 with `{"in_use": true, "purged": []}`, and `in-use` exited 4 with `What may hold it:` on stderr. The jsonl and `file-history/<uuid>` stayed (`__main__.py:146-148`).

A process that still has the lowercase uuid in its argv (`sh -c 'sleep 60; true' <uuid>`, argv0 `sh`, 57-character args, visible to `ps -eo pid=,ppid=,args=`) makes `conversation_in_use` true for the uppercase spelling and for the lowercase spelling (`claude.py:354`).

`purge_artifacts` itself has no in-use gate. It skips a live session file (`claude.py:323-327`) and still removes the other owned paths when called directly. The purge CLI and `stop_session.sh:290-298` both ask `conversation_in_use` first. Stop captures the in-use stderr with `2>&1 >/dev/null`, prints the records-preserved sentence, and exits 4. The passthrough `raise SystemExit(1)` is `stop_session.sh:327`. The stop SKILL.md exit-4 row (line 65) says the records are preserved and the session itself may already be down. `tests/data/skill_code_blocks.json` is unchanged since `6f4f40a` and still points that passthrough at `stop_session.sh:327`.

## Tests

Pytest used the control-plane venv, `PYTHONDONTWRITEBYTECODE=1`, `-p no:cacheprovider`, and `--basetemp` `/tmp/mam916-916abd41-pybase`. Inherited `HERDR_*`, `MAM_*`, `MQTT_*`, `SKS_*`, `WORKSPACE_ROOT`, `DELEGATE_JOB_LOGS_DIR`, `HOME_DIR`, `CLAUDE_PROJECT_DIR`, `CLAUDE_CONFIG_DIR`, `CLAUDE_CODE_TMPDIR`, `CODEX_HOME`, and `PYTHONPATH` were dropped. The suite's own fixtures then point `HOME` at the test tmp.

On the snapshot, 149 tests ran in 39.61 s: 2 failed, 146 passed, 1 skipped. Modules: `tests/test_issue31_purge_residual.py`, `tests/test_a4_adapter_contract.py`, `tests/test_issue42_skill_blocks.py`, `tests/test_issue55_agent_homes.py`. The skip is `test_claude_skills_link_resolves_to_agents_skills` (`tests/test_issue42_skill_blocks.py:266`), because `.claude/skills` is absent in this worktree. The issue-31 cases for a malformed id including `memory`, a linked directory, a linked orphan the CLI must report, NaN/`10**400`/bool `startedAt`, the UTC lstart mock, `_SYSTEM_TMP` staying inside the test, and the stop exit-4 text all passed. So did the a4 composite purge and the issue-55 home guard.

Both failures are `test_any_spelling_of_the_uuid_is_the_lowercase_session` (upper and mixed) at `tests/test_issue31_purge_residual.py:318`. The asserts above that line passed: the uppercase id was in use through the session file, purge and in-use both exited 4, and the owned files stayed. Line 315 then starts `sh -c "sleep 120" <lowercase-uuid>`. Bash 3.2 replaces a one-command `-c` script with that command. `ps` shows argv0 `sleep` and an 8-character argument string, and the uuid is gone. `conversation_in_use` of the uppercase id is false, which is what line 318 asserts against. The `sleep 60; true` form keeps the uuid and the same call returns true. The check at `claude.py:354` sees a command line that still carries the lowercase id. The process this test starts has already dropped it.

The same new tests copied onto an archive of `6f4f40a` fail on the pre-fix behavior. That archive is a separate clone. One line, `_SYSTEM_TMP = "/tmp"`, was added there so the new autouse fixture could patch a name `6f4f40a` does not define. `_tmp_roots` in that commit still hardcodes `/tmp` and does not read the name. `purge_artifacts("memory")` returned a `session-env/memory` path (`test_issue31_purge_residual.py:285`). The linked-dir purge returned removed paths (`:351`). The CLI asked about a leftover behind a link did not report that residual (`:373`). NaN, a digit string, and `True` were stale for a live pid (`:539`), and the live-holder purge was allowed through (`:556`). An uppercase id was outside `conversation_in_use` (`:307`). 21 failed, 13 passed, in 2.98 s. The real `/tmp/claude-<uid>` entry count stayed 7.

The in-use gate in `stop_session.sh` still runs for every agent that has a purge uuid, agy included. That was already true at `6f4f40a`.

After the report, snapshot porcelain is still empty, the snapshot still has no `.mam`, and control-plane porcelain is still empty at `26e2c43`. The herdr config mtime is still 1784456394.

[VERDICT: NOT PASS]