diff --git a/backend/tests/test_sprint129_operator_yolo_training_dataset.py b/backend/tests/test_sprint129_operator_yolo_training_dataset.py
index b4a5b1b1..79a9ec10 100644
--- a/backend/tests/test_sprint129_operator_yolo_training_dataset.py
+++ b/backend/tests/test_sprint129_operator_yolo_training_dataset.py
@@ -64,6 +64,9 @@ def test_operator_yolo_train_smoke_script_contract() -> None:
     assert "from ultralytics import YOLO" in script
     assert "model.train" in script
     assert "plots=False" in script
+    assert "seed_ultralytics_font" in script
+    assert "DejaVuSans.ttf" in script
+    assert "Arial.ttf" in script
     assert "training_summary.json" in script
     assert "download" not in script.lower()
     assert "fixture_mode" not in script
diff --git a/docs/CODEX_EXECUTION_LOG.md b/docs/CODEX_EXECUTION_LOG.md
index 980768af..b233b84d 100644
--- a/docs/CODEX_EXECUTION_LOG.md
+++ b/docs/CODEX_EXECUTION_LOG.md
@@ -23,7 +23,7 @@ Tested:
 - `bash -n scripts/train_operator_yolo_detector.sh` passed.
 - Live Tower export passed: `/app/storage/operator-data/yolo-building-dataset` contains 3 images and 1427 labels from the current Geel/Mol/Turnhout samples.
 - Live Tower training smoke passed with the existing `/app/models/yolov8n.pt` base model and wrote `/app/models/geointel-building-yolov8n-smoke.pt`.
-- The first live smoke showed Ultralytics fetching an auxiliary plot font. The wrapper now sets `plots=False` so the operator smoke path does not invoke plot/font network behavior.
+- The first live smoke showed Ultralytics fetching an auxiliary plot font. The wrapper now sets `plots=False` and seeds `Arial.ttf` from an existing local system font before importing Ultralytics so the operator smoke path does not invoke plot/font network behavior.
 
 Open:
 - Run the exporter and training smoke inside the AI-enabled Tower runtime, then benchmark the trained artifact through the existing multi-sample Detection + QA matrix.
diff --git a/scripts/train_operator_yolo_detector.sh b/scripts/train_operator_yolo_detector.sh
index 8eeea724..c3dce548 100644
--- a/scripts/train_operator_yolo_detector.sh
+++ b/scripts/train_operator_yolo_detector.sh
@@ -80,6 +80,25 @@ import os
 import shutil
 from pathlib import Path
 
+
+def seed_ultralytics_font() -> None:
+    font_candidates = [
+        Path("/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf"),
+        Path("/usr/share/fonts/truetype/liberation2/LiberationSans-Regular.ttf"),
+        Path("/usr/share/fonts/truetype/freefont/FreeSans.ttf"),
+    ]
+    source_font = next((font for font in font_candidates if font.exists()), None)
+    if source_font is None:
+        return
+    config_root = Path(os.environ.get("YOLO_CONFIG_DIR", str(Path.home() / ".config")))
+    target_font = config_root / "Ultralytics" / "Arial.ttf"
+    target_font.parent.mkdir(parents=True, exist_ok=True)
+    if not target_font.exists():
+        shutil.copy2(source_font, target_font)
+
+
+seed_ultralytics_font()
+
 from ultralytics import YOLO
 
 dataset_yaml = Path(os.environ["DATASET_YAML"])