diff --git a/tools/compress-assets.sh b/tools/compress-assets.sh
index f76dea8..f0bf027 100755
--- a/tools/compress-assets.sh
+++ b/tools/compress-assets.sh
@@ -20,6 +20,11 @@ set -euo pipefail
 SITE_DIR="${1:-_site}"
 MIN_SIZE="${MIN_SIZE:-1024}"  # bytes
 
+if [[ ! "$MIN_SIZE" =~ ^[0-9]+$ ]]; then
+    echo "compress-assets: MIN_SIZE must be a positive integer (got '$MIN_SIZE')" >&2
+    exit 1
+fi
+
 if [ ! -d "$SITE_DIR" ]; then
     echo "compress-assets: directory '$SITE_DIR' not found" >&2
     exit 1
diff --git a/tools/extract-dimensions.py b/tools/extract-dimensions.py
index d6a79d1..04017a4 100755
--- a/tools/extract-dimensions.py
+++ b/tools/extract-dimensions.py
@@ -99,7 +99,9 @@ def _walk_one_root(root: Path, counters: dict[str, int]) -> None:
         try:
             data = _read_dimensions(image)
         except Exception as e:  # noqa: BLE001 — keep walking
+            import traceback
             print(f"extract-dimensions: {image}: {e}", file=sys.stderr)
+            traceback.print_exc(file=sys.stderr)
             counters["failed"] += 1
             continue
 
diff --git a/tools/extract-exif.py b/tools/extract-exif.py
index 86078b0..73f7b25 100755
--- a/tools/extract-exif.py
+++ b/tools/extract-exif.py
@@ -289,7 +289,7 @@ def _read_exif_via_pillow(image: Path) -> dict[str, Any]:
                 out["width"] = width
             if isinstance(height, int) and height > 0:
                 out["height"] = height
-            exif = img._getexif() or {}
+            exif = img.getexif() or {}
     except Exception:  # noqa: BLE001 — corrupt EXIF should not abort the walk
         return out
 
@@ -422,7 +422,9 @@ def main() -> int:
         try:
             data = _read_one(image)
         except Exception as e:  # noqa: BLE001 — keep walking
+            import traceback
             print(f"extract-exif: {image}: {e}", file=sys.stderr)
+            traceback.print_exc(file=sys.stderr)
             failed += 1
             continue
 
diff --git a/tools/extract-palette.py b/tools/extract-palette.py
index 7a05a25..601824a 100755
--- a/tools/extract-palette.py
+++ b/tools/extract-palette.py
@@ -103,7 +103,9 @@ def main() -> int:
         try:
             palette = _extract_palette(image)
         except Exception as e:  # noqa: BLE001 — keep walking
+            import traceback
             print(f"extract-palette: {image}: {e}", file=sys.stderr)
+            traceback.print_exc(file=sys.stderr)
             failed += 1
             continue
 
diff --git a/tools/import-photo.sh b/tools/import-photo.sh
index c4598e4..45ad38b 100755
--- a/tools/import-photo.sh
+++ b/tools/import-photo.sh
@@ -52,6 +52,11 @@ ORIGINAL="$1"
 SLUG="$2"
 shift 2
 
+if [[ ! "$SLUG" =~ ^[a-z0-9-]+$ ]]; then
+    echo "import-photo: invalid slug '$SLUG' (must be lowercase a-z, 0-9, hyphens only)" >&2
+    exit 1
+fi
+
 TITLE=""
 while [ "$#" -gt 0 ]; do
     case "$1" in
@@ -118,7 +123,8 @@ magick "$ORIGINAL" \
     -resize '2400x2400>' \
     -colorspace sRGB \
     -quality 85 \
-    "$TARGET"
+    "$TARGET" \
+    || { echo "import-photo: magick resize failed for $ORIGINAL → $TARGET" >&2; exit 1; }
 chmod 644 "$TARGET"
 
 # ---------------------------------------------------------------------------
@@ -141,7 +147,8 @@ fi
 # ---------------------------------------------------------------------------
 
 echo "import-photo: stripping EXIF from delivered file..."
-magick mogrify -strip "$TARGET"
+magick mogrify -strip "$TARGET" \
+    || { echo "import-photo: magick mogrify -strip failed for $TARGET (EXIF NOT stripped)" >&2; exit 1; }
 
 # ---------------------------------------------------------------------------
 # Step 4: extract palette (does its own walk; idempotent on already-done photos)