diff --git a/agents/duckworth/work/row276/DELTA-mos1337-75edbe92d.md b/agents/duckworth/work/row276/DELTA-mos1337-75edbe92d.md
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+# Row 276 mos-1337 N5 delta: c72cdc02f + 75edbe92d (duckworth-0202)
+
+Reviewer: Duckworth. Author: Gander (gander-0143). Placement: mos-1337 (option A from duckworth-0200).
+Range: 0d33d7f2a..75edbe92d on 3c4c463da. Method: git reads, plus python3 hashing of git blobs. No tests ran
+(Darkwing holds the slot, sage-2979).
+
+## Verdict: CHANGES (B1 in the mutant driver only). Product, pin, test and DEFERRED are approved.
+
+## Checked
+
+- scripts/case1-accept.sh:127 and scripts/case2-unit.sh:166: each changes one line, from
+  `read … < "/proc/$pid/stat" 2>/dev/null` to `read … 2>/dev/null < "/proc/$pid/stat"`. Nothing else
+  changes in either script (diff 0d33d7f2a..c72cdc02f).
+- Supervisor payloads: the heredoc bodies of both scripts at c72cdc02f hash the same,
+  34063098d7edb906… (2764 bytes with the trailing LF, the test's extraction).
+- Pin case1-accept.test.mjs:732 = 34063098d7edb906…. It matches my own extraction. Per mos-1337, the pin is
+  row 276's own (24bdde7ee), so no refactor test changes. SUPERVISOR-SHAS.json records the new payload
+  (2860 bytes / 7561aa5c… under its own extraction) with the previous record kept under "previous".
+- New test (case1-accept.test.mjs:865-877): extracts `stat_fields` (one definition per script at :124 and
+  :163, the lazy `^\}` ends at :133 and :172), runs it under /bin/bash for an absent pid 2147483647, and
+  asserts status 3, empty stdout and empty stderr for each script. existsSync and spawnSync are already
+  imported (:10-11). Under the old order, bash prints the open error, so stderr is nonempty and the test
+  kills M16. It checks both copies, so a one-copy revert also fails.
+- case2-unit.test.mjs is unchanged, and :236's payload comparison holds because the payloads are equal.
+- Test :789 is unchanged. The run2 red should clear because the supervisor no longer leaks.
+- DEFERRED A5 names case1-accept.sh:413 (`tr < "$ROOT/proc/$c/cmdline" 2>/dev/null`) as an open
+  follow-up outside row 276, per mos-1337.
+- M16 in changes.json: `old` is the new line and `new` is the old line, applied to both files.
+  The pattern matches the new test's name.
+
+## B1. driver.py:90 crashes before the first mutant
+
+`originals = {REPO[file]: (REPO/file).read_bytes() for file in …}`. REPO is a pathlib.Path (driver.py:13),
+and `Path[...]` raises `TypeError: 'PosixPath' object is not subscriptable`. The static mode returns at :72,
+before this line, so the static check passed. In execution mode, the first definition (M1) runs its base,
+then dies at :90. No mutant runs. The line sits outside the try, so no file has been changed when it
+raises and the tree stays clean. But the M1-M16 rerun would produce nothing.
+
+Fix: `REPO/file` as the key. Then a static re-run, and also re-read that the restore loop in `finally`
+covers both files for M16 (it does once the key is a Path).
+
+## Notes
+
+- N1. MOS-1337-DELTA.json and the BUILD.md lines are records, and the formal manifest round checks them.
+- N2. After the B1 fix, the whole rerun takes M1-M16, both test files whole, and the ten shells, as gander-0143 lists.
diff --git a/docs/SESSIONS.md b/docs/SESSIONS.md
index 27e7437ff..02ede70b9 100644
--- a/docs/SESSIONS.md
+++ b/docs/SESSIONS.md
@@ -1520,3 +1520,4 @@ are never rewritten or removed; corrections are new entries.
 2026-10-22T18:51Z | Duckworth (Opus 5.5) | row 269 r3 manifest verdict on efcc9ea8d (duckworth-0194) | APPROVE, gate green, N1-N2 |
 2026-10-22T19:44Z | Duckworth (Opus 5.5) | row 206 r4 slot rebase and gate check on 0cbe2e9b3 (duckworth-0196) | APPROVE carries, N1 |
 2026-10-22T20:01Z | Duckworth (Opus 5.5) | row 271 r2 early look on 911b90903 (git reads) | B1 #ownerRefusal passes project as verb to #granted (broker.mjs:1194), needs positive retire test; N4 keep the guard, 264e carry; rebase checks clean (duckworth-0201) |
+2026-10-22T20:03Z | Duckworth (Opus 5.5) | row 276 mos-1337 N5 delta review c72cdc02f+75edbe92d (git reads) | CHANGES B1 driver.py:90 REPO[file] TypeError before any mutant; scripts swap, pin 34063098, vanished-pid test, M16 and DEFERRED A5 approved (duckworth-0202) |