diff --git a/docker/decoder/sylph-decoder b/docker/decoder/sylph-decoder
index df75430e..2ba16652 100755
--- a/docker/decoder/sylph-decoder
+++ b/docker/decoder/sylph-decoder
@@ -123,7 +123,16 @@ docker_args() {
     # emulator and scrape /dev/shm to get at it. An earlier belief that this
     # file was STALE was tested and refuted -- it is current.
     -v "${SYLPH_PE:-$PROJECT/Project Sylpheed - Arc of Deception (USA, Europe) (En,Ja).pe}:/image/sylpheed.pe:ro"
-    -e "SYLPHEED_DB=/xenia-rs/sylpheed.db"
+    # 🔴 THE DISASSEMBLY DATABASE. This used to be read from the xenia-rs clone
+    # (`SYLPHEED_DB=/xenia-rs/sylpheed.db`). That repo is retired, its directory
+    # is gone, and the mount that served it was removed -- so the variable named
+    # a path that did not exist and `zq.py` had nothing to open. The database now
+    # lives beside the repo as a build artefact; mounted at the container's repo
+    # root, which is where `zq.py` looks when `$SYLPHEED_DB` is unset.
+    #
+    # Read-only on purpose: the host owns it, DuckDB takes an exclusive lock to
+    # write, and two agents plus the human sharing one file would corrupt it.
+    # Regenerating means writing elsewhere and pointing `$SYLPHEED_DB` at it.
     -e "SYLPHEED_PE=/image/sylpheed.pe"
     -e "SYLPHEED_IMAGE_BASE=0x82000000"
     # 🔴 EVIDENCE IS SHARED, NOT COMMITTED (issue #49). Each agent works in its
@@ -276,6 +285,20 @@ docker_args() {
     echo "==> NOTE: no ISO at $_iso -- Canary has nothing to boot." >&2
   fi
 
+  # The disassembly database. `zq.py` looks at the repo root when $SYLPHEED_DB
+  # is unset, so mounting it there needs no environment variable at all -- which
+  # is what the dead `/xenia-rs/sylpheed.db` variable taught: a path in an env
+  # var and a path in a mount drift apart silently.
+  _db="${SYLPH_DB:-$PROJECT/Sylpheed/sylpheed.db}"
+  if [ -f "$_db" ]; then
+    _out+=(-v "$_db:/work/sylpheed.db:ro")
+  else
+    echo "==> NOTE: no sylpheed.db at $_db -- /sylph-dis and zq.py cannot run." >&2
+    echo "    build one:  cargo run --release -p sylpheed-xexdb --bin sylph-xexdb -- \\" >&2
+    echo "                  dis \"\$SYLPH_ISO\" --db sylpheed.db --analyze sql --quiet" >&2
+    echo "    then re-apply the RE names with tools/apply_re_symbols.sql" >&2
+  fi
+
   # ── GPU ──
   # Three distinct cases, and conflating them is how you end up believing you
   # have hardware Vulkan while actually running llvmpipe:
diff --git a/docs/agents/decoder-loop.md b/docs/agents/decoder-loop.md
index 04a6804a..50838b2b 100644
--- a/docs/agents/decoder-loop.md
+++ b/docs/agents/decoder-loop.md
@@ -56,11 +56,23 @@ rather than left in a document you might not reach.
 | path | what | env |
 |---|---|---|
 | `/image/sylpheed.pe` | the decompressed executable image | `SYLPHEED_PE` |
-| `/xenia-rs/sylpheed.db` | a disassembly database, 586 MB | `SYLPHEED_DB` |
+| `sylpheed.db` at the repo root | the disassembly database, 337 MB | — (`zq.py` finds it; `$SYLPHEED_DB` only to override) |
+| `/canary/build/bin/Linux/Release/xenia_canary` | the built oracle, inside the `/canary` mount | — |
 | `/disc` | the extracted disc | `SYLPHEED_DISC` |
 | `/iso/game.iso` | the retail ISO Canary boots | `SYLPH_ISO` |
 | `/canary` | the Canary source, read-write | `XENIA_SRC` |
 
+⚠️ **The database is read-only and is NOT in git** — it is a build artefact, and
+`docs/re/captures/` is the same (issue #49). If either is missing the launcher
+says so and prints the command that builds it. Query the database with
+`python3 tools/zq.py …`, never by reading a disassembly dump.
+
+⚠️ **The built Canary carries the `RE-INPUT`/`RE-DRAW` instrumentation but NOT
+the `audit_61` guest-PC branch probe** — that lives only on
+`auto/canary-instrumentation-snapshot-2026-07-28` and `phase-a-tracing`
+(fork issue #1), so a probe run needs those two commits on `sylpheed-re` and a
+rebuild first. Verified by `strings` on the binary, not assumed.
+
 **The `.pe` is a flat VA dump**: file offset = `VA - 0x82000000`. Reading
 `0x820A1630` is `seek(0xA1630)`. No XEX decrypt, no LZX, **no booted emulator** —
 dumping guest memory works but makes the whole static corpus depend on a running