diff --git a/tools/validate.py b/tools/validate.py
index 09bb309..c48e09e 100644
--- a/tools/validate.py
+++ b/tools/validate.py
@@ -366,7 +366,12 @@ def run_selftest(verbose=False):
 
 
 def load_entries():
-    return sorted((ROOT / "codex").rglob("*.yaml"))
+    out = []
+    for p in sorted((ROOT / "codex").rglob("*.yaml")):
+        if p.name.startswith("_"):
+            continue  # dataset files (e.g. _f2p-alch-catalog.yaml) are not entries
+        out.append(p)
+    return out
 
 
 def main():