Add feature extraction and labeling thresholds to config

Introduces new configuration options for feature extraction and program labeling, including thresholds for suggesting simplification, including change descriptions, and labeling implementations as concise or comprehensive. Updates PromptConfig and PromptSampler to use these new parameters, while maintaining backward compatibility with the deprecated code_length_threshold.

Author: codelion

configs/default_config.yaml

@@ -68,6 +68,13 @@ prompt:
   max_artifact_bytes: 20480           # Maximum artifact size in bytes (20KB default)
   artifact_security_filter: true      # Apply security filtering to artifacts
 
+  # Feature extraction and program labeling thresholds
+  # These control how the LLM perceives and categorizes programs
+  suggest_simplification_after_chars: 500     # Suggest simplifying if program exceeds this many characters
+  include_changes_under_chars: 100           # Include change descriptions in features if under this length  
+  concise_implementation_max_lines: 10        # Label as "concise" if program has this many lines or fewer
+  comprehensive_implementation_min_lines: 50  # Label as "comprehensive" if program has this many lines or more
+
   # Note: meta-prompting features are not yet implemented
 
 # Database configuration

openevolve/config.py

@@ -142,8 +142,14 @@ class PromptConfig:
     max_artifact_bytes: int = 20 * 1024  # 20KB in prompt
     artifact_security_filter: bool = True
 
-    # Improvement areas
-    code_length_threshold: Optional[int] = 500
+    # Feature extraction and program labeling
+    suggest_simplification_after_chars: Optional[int] = 500  # Suggest simplifying if program exceeds this many characters
+    include_changes_under_chars: Optional[int] = 100  # Include change descriptions in features if under this length
+    concise_implementation_max_lines: Optional[int] = 10  # Label as "concise" if program has this many lines or fewer
+    comprehensive_implementation_min_lines: Optional[int] = 50  # Label as "comprehensive" if program has this many lines or more
+    
+    # Backward compatibility - deprecated
+    code_length_threshold: Optional[int] = None  # Deprecated: use suggest_simplification_after_chars
 
 
 @dataclass

openevolve/prompt/sampler.py

@@ -171,7 +171,9 @@ def _identify_improvement_areas(
         improvement_areas = []
 
         # Check program length
-        if self.config.code_length_threshold and len(current_program) > self.config.code_length_threshold:
+        # Support both old and new parameter names for backward compatibility
+        threshold = self.config.suggest_simplification_after_chars or self.config.code_length_threshold
+        if threshold and len(current_program) > threshold:
             improvement_areas.append(
                 "Consider simplifying the code to improve readability and maintainability"
             )
@@ -499,7 +501,7 @@ def _extract_unique_features(self, program: Dict[str, Any]) -> str:
         metadata = program.get("metadata", {})
         if "changes" in metadata:
             changes = metadata["changes"]
-            if isinstance(changes, str) and len(changes) < 100:
+            if isinstance(changes, str) and self.config.include_changes_under_chars and len(changes) < self.config.include_changes_under_chars:
                 features.append(f"Modification: {changes}")
 
         # Analyze metrics for standout characteristics
@@ -521,9 +523,9 @@ def _extract_unique_features(self, program: Dict[str, Any]) -> str:
                 features.append("NumPy-based implementation")
             if "for" in code_lower and "while" in code_lower:
                 features.append("Mixed iteration strategies")
-            if len(code.split("\n")) < 10:
+            if self.config.concise_implementation_max_lines and len(code.split("\n")) <= self.config.concise_implementation_max_lines:
                 features.append("Concise implementation")
-            elif len(code.split("\n")) > 50:
+            elif self.config.comprehensive_implementation_min_lines and len(code.split("\n")) >= self.config.comprehensive_implementation_min_lines:
                 features.append("Comprehensive implementation")
 
         # Default if no specific features found