Prompt: repeat "a cute" per animal for clearer multi-animal scenes

Split _join into _join_animals / _join_places. Animals now read
"puppy, a cute kitten and a cute bunny" so the model renders each as a
distinct cute subject (helps 2–3 animal rewards).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

image_generator.py

@@ -210,7 +210,17 @@ NUMZOO_STYLE = (
 # Prompt builder
 # ---------------------------------------------------------------------------
 
-def _join(parts: list[str]) -> str:
+
+def _join_animals(parts: list[str]) -> str:
+    """Join 1–3 phrases: 'a', 'a and b', 'a, b and c'."""
+    if len(parts) == 1:
+        return parts[0]
+    if len(parts) == 2:
+        return f"{parts[0]} and a cute {parts[1]}"
+    return f"{parts[0]}, a cute {parts[1]} and a cute {parts[2]}"
+
+
+def _join_places(parts: list[str]) -> str:
     """Join 1–3 phrases: 'a', 'a and b', 'a, b and c'."""
     if len(parts) == 1:
         return parts[0]
@@ -224,8 +234,8 @@ def build_subject(animals: list[str], places: list[str]) -> str:
     so training captions and live prompts use the exact same structure & vocabulary."""
     animal_list = animals[:3] if animals else [random.choice(list(ANIMAL_MAP))]
     place_list  = places[:3]  if places  else [random.choice(list(PLACE_MAP))]
-    animal_text = _join([ANIMAL_MAP.get(a, "bunny") for a in animal_list])
-    place_text  = _join([PLACE_MAP.get(p, "in a magical garden") for p in place_list])
+    animal_text = _join_animals([ANIMAL_MAP.get(a, "bunny") for a in animal_list])
+    place_text  = _join_places([PLACE_MAP.get(p, "in a magical garden") for p in place_list])
     return f"A cute {animal_text} {place_text}"