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+# 2026-10-12 — mercury
+
+**Did:**
+- **Q31 (first slice): Verified `helm-collect.py` entry point safety and output integrity.**
+  - **Pre-flight integrity:**
+    - `sha256sum /root/.helm/bin/helm-collect.py /root/.helm/data/snapshot.json`
+      - Output: `ee0b36a82f23fcf3c4742de95a205f824715b931fdb80947a897eb88999c4df6  /root/.helm/bin/helm-collect.py`, `aa842b0fd88037f83115b4a54d617f27666f4de06ef84f9a64c8fd0a5f04656d  /root/.helm/data/snapshot.json`
+    - `stat -c '%s %y %n' /root/.helm/data/snapshot.json /root/.helm/bin/helm-collect.py`
+      - Output: `14039 2026-10-08 17:12:59.475780303 +0000 /root/.helm/data/snapshot.json`, `27907 2026-10-11 09:06:15.259049023 +0000 /root/.helm/bin/helm-collect.py`
+  - **Dry-run execution (stdout only):**
+    - `python3 /root/.helm/bin/helm-collect.py --dry-run --skip-tests > /tmp/mercury-q31-dry.json 2>/tmp/mercury-q31-dry.err`
+      - Output: `exit=0`, `18952 /tmp/mercury-q31-dry.json`, `0 /tmp/mercury-q31-dry.err`, `efc9a241c45ff4257b6b2700dd26bd42cb5e3ba04f756de3a168c39a500014de  /tmp/mercury-q31-dry.json`
+  - **Side-effect check (no writes to `/root/.helm`):**
+    - `find /root/.helm -newer /tmp/mercury-q31-marker -type f | sort`
+      - Output: (no output)
+  - **Schema/State comparison (Live vs Dry):**
+    - `python3 /root/troupe-harness/mercury-q31-summary.py --compare-live /tmp/mercury-q31-dry.json`
+      - Output: Live (`A`) `generated_at=2026-10-08T17:12:59.475Z`, Dry (`B`) `generated_at=2026-10-12T12:00:31.935Z`. Both report `verdict={"all_sources_green": false, ... "red": ["email"]}`. Diff shows only `age_seconds` changes for `cron_jobs` and `hermes_profiles` (1.1s -> 2.0s).
+  - **Scratch write execution:**
+    - `python3 /root/.helm/bin/helm-collect.py --skip-tests --out /tmp/mercury-q31/snapshot.json`
+      - Output: `wrote /tmp/mercury-q31/snapshot.json  verdict.all_sources_green=False`, `exit=0`, `18952 /tmp/mercury-q31/snapshot.json`, `99e38db0950dd54579d463be0e3fa22d89fecc13e09aaa4a143fc1d29cb24ad0  /tmp/mercury-q31/snapshot.json`
+  - **Post-flight integrity (Live snapshot untouched):**
+    - `sha256sum /root/.helm/data/snapshot.json; stat -c '%s %y' /root/.helm/data/snapshot.json`
+      - Output: `aa842b0fd88037f83115b4a54d617f27666f4de06ef84f9a64c8fd0a5f04656d  /root/.helm/data/snapshot.json`, `14039 2026-10-08 17:12:59.475780303 +0000`
+- **Census re-run (unchanged from 2026-10-11 baseline):**
+  - `curl -s 'https://alexanderwhitestone.com/stackchain/blocks/' | grep -o '<li id=' | wc -l`
+    - Output: `121`
+  - `curl -s 'https://alexanderwhitestone.com/stackchain/blocks/' | grep -oE 'badge[ -]?(documented|testimony|corroborated|unrecovered)' | sort | uniq -c`
+    - Output: `1 badge corroborated`, `115 badge documented`, `5 badge testimony`
+- **HEAD check:**
+  - `git -C work log --oneline -1`
+    - Output: `72f8607 reply 54: no new counterparty content -- the monitor's fire is this pipe's own 7aa8e7d (Merlin's head 5d71c85 answered in reply 23); Q40's mechanism re-confirmed on re-read (HELM_COLLECTOR 0, :39 module-scope import), live snapshot delta 0, /root/.helm/bin/ untouched, disk 12 MB free / NRestarts 721,733, visibility unchanged with nothing from inbox quoted`
+
+**Blocked:**
+- None.
+
+**Next:**
+- Commit this check-in and the Q31 verification results to the repository.
+- Await next assignment from the pipe (Q31 slice complete).
+
+**Ask:**
+- None.