diff --git a/REQUIREMENTS.md b/REQUIREMENTS.md
index c269a632..650ed9ac 100644
--- a/REQUIREMENTS.md
+++ b/REQUIREMENTS.md
@@ -33,9 +33,15 @@ Before booting/testing:
 Install the baseline tools:
 
 ```sh
-sudo pkg install -y curl node24 npm-node24 sudo
+sudo pkg install -y curl node24 npm-node24 sudo go rust
 ```
 
+`go` and `rust` are build-host toolchains, not image packages: `go` builds the
+zot agent binary and `rust` builds the Colibri release binaries. `build.sh`
+stages those prebuilt binaries (it does not compile them itself) and fails
+preflight if they are missing — so build them on the host first. They are not
+installed onto the image.
+
 `build.sh` sets its own FreeBSD tool PATH:
 
 ```text
diff --git a/build.sh b/build.sh
index ed5e415a..84058fa1 100755
--- a/build.sh
+++ b/build.sh
@@ -340,6 +340,8 @@ preflight_colibri_artifacts() {
     for _colibri_bin in colibri-daemon colibri colibri-smoke-agent colibri-mcp; do
         if [ ! -x "${_resolved_colibri_artifact_dir}/${_colibri_bin}" ]; then
             echo "ERROR: Colibri release binary missing: ${_resolved_colibri_artifact_dir}/${_colibri_bin}"
+            command -v cargo >/dev/null 2>&1 || \
+                echo "       NOTE: rust toolchain not found on this host — install it: pkg install rust"
             echo "       Build first: (cd ${_resolved_colibri_repo} && cargo build --workspace --release)"
             echo "       Or set FEATURE_COLIBRI=NO to skip Colibri staging."
             exit 1
@@ -372,6 +374,8 @@ preflight_zot_artifacts() {
     resolve_zot_paths
     if [ ! -x "${_resolved_zot_artifact_dir}/zot" ]; then
         echo "ERROR: Colibri agent binary missing: ${_resolved_zot_artifact_dir}/zot"
+        command -v go >/dev/null 2>&1 || \
+            echo "       NOTE: go toolchain not found on this host — install it: pkg install go"
         echo "       The agent has no FreeBSD release — build it first:"
         echo "       (cd ${_resolved_zot_repo} && git checkout ${ZOT_VERSION:-v0.2.29} && \\"
         echo "          GOOS=freebsd GOARCH=amd64 go build -trimpath -o bin/zot ./cmd/zot)"