diff --git a/FABRIC-3.6.md b/FABRIC-3.6.md
index 23239bd0..b9be1140 100644
--- a/FABRIC-3.6.md
+++ b/FABRIC-3.6.md
@@ -58,6 +58,36 @@ early is this project's most repeated failure.
 
 ---
 
+## Pre-flight — establish the baseline before anything changes
+
+**Branch state at open (2026-09-19):** `claude/starshipos-tripod-kernel-reshuffle-itbjns`, head
+`3a4e5cf`, **working tree clean, pushed, 33 commits ahead of `master`** — all documentation, no
+code. `master` is unmoved at `e56974e`, so the branch remains a clean fast-forward. **Execution
+starts from this commit.**
+
+- [ ] **0.0** — **Three-ISA baseline smoke test on the unmodified branch.**
+      `make -f Makefile.starkernel ARCH=<arch> clean qemu` for amd64, aarch64, riscv64 — one at
+      a time, in the foreground, per `.claude/CLAUDE.md`.
+      *Check:* all three reach `zuse)ok>`; zero `UNKNOWN WORD`; logs committed under
+      `logs/<timestamp>/<arch>/`; **record each `dict_hash` and confirm the three are
+      identical.**
+
+**Why this is a gate and not a formality.** Every task in this document takes the
+three-architecture boot as its acceptance (§XXXIV). **Without a known-good baseline captured
+first, the first red boot is ambiguous** — pre-existing fault or something task 0.2 just did?
+This project has been bitten by exactly that ambiguity before (`FABRIC-3.md` §XXVI: "the
+lockdown was never broken — wrong VM tested"). The baseline is what makes every later
+acceptance run interpretable, and the recorded `dict_hash` triple is the reference every
+subsequent §XXXIV.6 divergence check compares against.
+
+**Not runnable in the session that wrote this document, and deliberately not faked.** Checked
+2026-09-19 in the authoring container: **no `qemu-system-x86_64`, `-aarch64` or `-riscv64`; no
+`aarch64-linux-gnu-gcc` or `riscv64-linux-gnu-gcc`; no OVMF/AAVMF firmware.** Only host `gcc`,
+`clang` and `lld` are present. **Task 0.0 must be run by Captain Bob on a machine with the real
+toolchain**, and its result recorded here before task 0.1 begins.
+
+---
+
 ## Phase 0 — Preparation (no behaviour change)
 
 **Gate:** all three architectures boot to `zuse)ok>`, `stadium_conserved()` true, no