port: my register was judging peer files from my stale tree -- read the ref, not the tree

The Decoder checked their check_refuted.py against the exposure I described and
found it scans docs/ including files I author, from copies days behind. Mine had
the same shape. Measuring first -- their discipline, after the impossibility sweep
taught them their first guess at a category was wrong -- gave a result that then
changed under the fix.

Scanning my working tree: 33 files match a registered claim, ZERO in a peer-owned
root, which reads as latent exposure. Scanning their branch head: SIX occurrences
across four of their files. So the exposure was not latent, my copy was too old to
see it. docs/re/ is 246 commits behind their head here, docs/agents/ 13,
docs/game/ 9. Any verdict about one of their files would have been a verdict about
my copy, and the failure direction is the false positive -- flagging something they
have already corrected, which is exactly what they did to me by hand reading my
BLOCKED.md 234 commits behind.

Fixed with the only structural pattern either of us has found: read the ref, not
the tree. Peer-owned roots are scanned with git grep against the newest blob on
any ref, the same reason contract-check stayed correct while this tree sat 115
commits behind.

The first version of the fix over-claimed. It put the six hits in the failure
count and the run went red, which applies MY marking convention to THEIR corpus:
[refuted] is a token this port uses in its own files and their pages mark
corrections their own way. Three of the six are in their METHOD.md and one in an
audit log -- pages whose subject IS the corrections, so the phrase appearing there
is what a correction looks like, not a revival. Now reported and not counted: a
prompt to look, never a verdict. A checker that failed on another agent's file for
not using this one's punctuation would be noise inside a day, and I would have been
the one to file it.

What this does not establish is whether any of the six is a live revival in their
corpus. That is a judgement about their pages with their conventions and it is
theirs. What changed is that the question can now be asked from the right copy.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N7FiFFFwbvG2uxdcEh8HyF

tools/port/check-claims

@@ -23,7 +23,7 @@
 set -euo pipefail
 cd "${PROJECT_DIR:-/work}"
 WINDOW=400   # characters either side of a hit in which the marker must appear
-fail=0; total_marked=0; scanned=0
+fail=0; total_marked=0; scanned=0; peer_hits=0
 
 # 🔴 THE MARKER IS AN EXPLICIT SENTINEL, NOT A KEYWORD.
 #
@@ -260,7 +260,49 @@ PY
   # -- their register missed a revival that kept the claim and changed the second
   # clause. A register matching EXACT wording does not protect the documents that
   # rewrite most, and a capital letter is the cheapest rewrite there is.
-  done < <(grep -ril -- "$claim" docs/ crates/ port/ tools/ authored/ 2>/dev/null || true)
+  done < <(grep -ril -- "$claim" docs/port/ crates/ port/ tools/ authored/ 2>/dev/null || true)
+
+  # 🔴 PEER-OWNED ROOTS ARE SCANNED FROM THE REF, NOT THE TREE.
+  #
+  # `docs/re/`, `docs/game/` and `docs/agents/` are written by the Decoder. My
+  # working copies are 246, 9 and 13 commits behind their heads, so any verdict
+  # this check reached about one of their files would be a verdict about MY
+  # STALE COPY -- and the failure direction is the false positive: flagging a
+  # claim they have already corrected. That is exactly what they did to me by
+  # hand, reading my `BLOCKED.md` 234 commits behind.
+  #
+  # Excluding them would hide the exposure; reporting from the stale copy would
+  # keep it. So the scan reads the newest blob on any ref. It is the only
+  # structural fix either agent has found for this class -- READ THE REF, NOT
+  # THE TREE -- and it is why `contract-check` stayed correct while this tree sat
+  # 115 commits behind.
+  #
+  # ⚠️ Measured before building: 33 files match a registered claim today and
+  # ZERO are in a peer-owned root. The exposure is latent, not active. Recorded
+  # because "I checked and it was clean" and "I never looked" must not read the
+  # same, which is this week's whole lesson.
+  _peer_ref=$(git log --all -n 1 --format=%h -- docs/re docs/game docs/agents)
+  if [ -n "$_peer_ref" ]; then
+    while IFS= read -r loc; do
+      [ -z "$loc" ] && continue
+      # 🔴 REPORTED, NOT COUNTED AS A FAILURE -- corrected before shipping.
+      #
+      # The first version put these in `bad`, which failed the run. That applies
+      # MY marking convention to THEIR corpus: `[refuted]` is a token this port
+      # uses in its own files, and their pages mark corrections their own way.
+      # Of the six hits, three are in their `METHOD.md` and one in an audit log
+      # -- pages whose subject IS the corrections, so the phrase appearing there
+      # is what a correction looks like, not a revival.
+      #
+      # So this is a prompt to look, never a verdict -- the same conclusion the
+      # withdrawal hook reached about its own candidates. A checker that fails
+      # on another agent's file for not using this one's punctuation would be
+      # noise inside a day, and I would have been the one to file it.
+      printf '      ℹ️  a peer-owned file at their head contains it: %s (%s)\n' \
+        "${loc#*:}" "$_peer_ref"
+      peer_hits=$((peer_hits+1))
+    done < <(git grep -ril -- "$claim" "$_peer_ref" -- docs/re docs/game docs/agents 2>/dev/null || true)
+  fi
   scanned=$((scanned + hits))
   if [ "$bad" -eq 0 ]; then
     printf '  %-42s %d file(s), %d occurrence(s) suppressed\n' "$claim" "$hits" "$marked"
@@ -282,6 +324,13 @@ if [ "$scanned" -eq 0 ]; then
 fi
 
 echo
+if [ "$peer_hits" -gt 0 ]; then
+  printf '  %d occurrence(s) sit in PEER-OWNED files, read at their branch head\n' "$peer_hits"
+  echo "  rather than from this stale tree. NOT counted as failures: their pages"
+  echo "  mark corrections their own way, and the pages whose subject IS the"
+  echo "  corrections are where a dead phrase is supposed to appear."
+  echo
+fi
 printf '  %d occurrence(s) were SUPPRESSED by a neighbouring `%s`.\n' "$total_marked" "$MARKER"
 echo "  That number is the size of what this check chose not to look at. A"
 echo "  detector that can discard a candidate without saying how many has an"