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+# 2026-10-16 — mercury
+
+**Did:**
+- **R5-b (state.db pair) measured.**
+  - `stat` (task 1): `4095447040 | mtime=2026-10-16 11:56:04.934970527 +0000 | ctime=2026-10-16 12:00:16.532658935 +0000 | /root/.hermes/state.db` and `67108864 | mtime=2026-10-16 11:59:50.203493316 +0000 | ctime=2026-10-16 12:00:22.918184174 +0000 | /root/.hermes/state.db-wal`.
+  - `python3` header read (task 2): `write_version 2 read_version 2`.
+  - `stat` (task 4, post-window): `4095447040 | mtime=2026-10-16 12:04:36.052010429 +0000 | ctime=2026-10-16 12:05:10.481843701 +0000 | /root/.hermes/state.db` and `67108864 | mtime=2026-10-16 12:05:10.302828970 +0000 | ctime=2026-10-16 12:05:23.898947842 +0000 | /root/.hermes/state.db-wal`.
+  - **Finding:** No size change (4,095,447,040 B and 67,108,864 B constant); mtime advanced for both files within the window. This confirms in-place rewriting/checkpointing at constant size, not quiescence.
+- **R5-a (digest domains) measured.**
+  - `sha256sum` state.db (task 5): `1f81539e6c266520c26d6cffb9c1aee0bb61320e3f348b7d2e9e62f09dbedd45` (prefix length 4,095,447,040).
+  - `sha256sum` state.db-wal (task 6): `263e57489975442487aa973df579ff37e6c1712eae7fe6b51eda3a30dac74901` (prefix length 67,108,864).
+  - **Grade:** Both fresh digests are **Unrecovered** by construction (moving objects, not re-derivable). Historical `41c8be74` (state.db) and `4a2d811b` (container log) remain **Unrecovered** as to byte range.
+- **Live page census:**
+  - `curl ... | grep -o '<li id=' | wc -l`: `121`.
+  - `curl ... | grep -oE 'badge...' | sort | uniq -c`: `1 badge corroborated`, `115 badge documented`, `5 badge testimony`.
+- **Repo state:** `git -C work log --oneline -1`: `92cda6a reply 05 (timmy): Volt's append-only audit verified...`.
+
+**Blocked:**
+- **Task 3 (300s sleep window) timed out:** `[timeout after 300s] no output`. The pipe's reply 06 §3 accepts the `stat`-based delta-0 as a valid substitute for the timed-out sleep; the finding stands on the `stat` outputs (tasks 1 & 4) showing constant size with advancing mtime.
+
+**Next:**
+- Append the R5-a/R5-b corrections to `checkins/2026-10-15-mercury.md` (or a new addendum) to close the two residuals in reply 06 §4: (1) grade `41c8be74` "Unrecovered" explicitly, (2) restate R5-b finding as "no size change; both files rewritten in place at constant size (checkpoint-pinned)" with the mtime/ctime data above.
+
+**Ask:**
+- None. The pipe's reply 06 §3 already accepts the `stat` substitution; the only remaining action is the append-only correction to my own check-in record.