def get_score_str(self, score: int) -> str:
     th_high = get_settings().pr_code_suggestions.get('new_score_mechanism_th_high', 9)
     th_medium = get_settings().pr_code_suggestions.get('new_score_mechanism_th_medium', 7)
+    if not isinstance(score, int) or score < 0:
+        return "Invalid"
     if score >= th_high:
         return "High"
     elif score >= th_medium:
         return "Medium"
     else:  # score < 7
         return "Low"

-if suggestion.get('score_why'):
+if 'score' in suggestion and 'score_why' in suggestion and isinstance(suggestion['score'], int) and isinstance(suggestion['score_why'], str):
     pr_body += f"<details><summary>Suggestion importance[1-10]: {suggestion['score']}</summary>\n\n"
     pr_body += f"__\n\nWhy: {suggestion['score_why']}\n\n"
     pr_body += f"</details>"

-th_high = get_settings().pr_code_suggestions.get('new_score_mechanism_th_high', 9)
-th_medium = get_settings().pr_code_suggestions.get('new_score_mechanism_th_medium', 7)
+pr_code_suggestions = get_settings().pr_code_suggestions or {}
+th_high = pr_code_suggestions.get('new_score_mechanism_th_high', 9)
+th_medium = pr_code_suggestions.get('new_score_mechanism_th_medium', 7)

-pr_body += f"__\n\nWhy: {suggestion['score_why']}\n\n"
+pr_body += f"__\n\nWhy: {suggestion.get('score_why', 'No explanation provided')}\n\n"

-score_int = int(suggestion['score'])
+score_int = int(suggestion.get('score', 0))

-pr_body += f"""<tr><td rowspan={num_suggestions}>{label.capitalize()}</td>\n"""
+pr_body += f"""<tr><td rowspan={max(num_suggestions, 1)}>{label.capitalize()}</td>\n"""

-score_int = int(suggestion['score'])
-score_str = f"{score_int}"
-if get_settings().pr_code_suggestions.new_score_mechanism:
-    score_str = self.get_score_str(score_int)
+score = suggestion.get('score')
+if score is not None:
+    score_int = int(score)
+    score_str = f"{score_int}"
+    if get_settings().pr_code_suggestions.new_score_mechanism:
+        score_str = self.get_score_str(score_int)
+else:
+    score_str = "N/A"

 def get_score_str(self, score: int) -> str:
+    if not 1 <= score <= 10:
+        raise ValueError("Score must be between 1 and 10")
     if score >= 9:
         return "High"
     elif score >= 7:
         return "Medium"
     else:  # score < 7
         return "Low"

+# At module level
+HIGH_IMPACT_THRESHOLD = 9
+MEDIUM_IMPACT_THRESHOLD = 7
+
 def get_score_str(self, score: int) -> str:
-    if score >= 9:
+    if score >= HIGH_IMPACT_THRESHOLD:
         return "High"
-    elif score >= 7:
+    elif score >= MEDIUM_IMPACT_THRESHOLD:
         return "Medium"
-    else:  # score < 7
+    else:
         return "Low"