diff --git a/README.md b/README.md
index ba39f14a..082b88f9 100644
--- a/README.md
+++ b/README.md
@@ -27,6 +27,10 @@ Quick pointers
 - Emit object with harness: set `NYASH_LLVM_USE_HARNESS=1` and `NYASH_LLVM_OBJ_OUT=<path>` (defaults in tools use `tmp/`).
 - Run PyVM: `NYASH_VM_USE_PY=1 $NYASH_BIN --backend vm apps/APP/main.nyash`.
 
+Program(JSON v0) → MIR(JSON)
+- Convert a Stage‑B Program(JSON v0) file to MIR(JSON):
+  - `$NYASH_BIN --json-file /path/program.json --program-json-to-mir /tmp/mir.json`
+
 Dev shortcuts (Operator Boxes & JSON smokes)
 - One‑shot JSON verification (dev, Operator Boxes ON): `./tools/opbox-json.sh`
 - Run quick profile with Operator Boxes: `./tools/opbox-quick.sh`