LivingAgents/docs/trait-system.md

Dynamic Trait Development System

An incremental personality development system that builds character traits from experiences and observations.

🎯 System Philosophy

Characters develop personality traits naturally through their experiences, rather than having fixed, predefined personalities. This creates more realistic, evolving characters that feel genuinely shaped by their interactions.

🧬 Trait Structure

CharacterTrait Data Model

@dataclass
class CharacterTrait:
    name: str  # Single word (shy, romantic, studious)
    strength: int  # 1-10 intensity scale
    description: str  # How trait manifests behaviorally
    updated: datetime  # When last modified

Integration with Character

@dataclass
class Character:
    # ... other fields ...
    traits: List[CharacterTrait] = field(default_factory=list)

    def has_trait(self, trait_name: str) -> bool

        def get_trait(self, trait_name: str) -> Optional[CharacterTrait]

        def get_trait_strength(self, trait_name: str) -> int

🔄 Incremental Development Process

1. Observation Analysis

When new memories are added, system analyzes trait impact:

# Every new observation is evaluated
memory = await agent.add_observation("I felt nervous talking to Emma")

# System asks: Does this reveal or change personality traits?
# - Create new traits?
# - Strengthen existing traits? 
# - Weaken contradicting traits?
# - No significant impact?

2. Trait Impact Assessment

Uses structured LLM analysis to determine changes:

Input: New observation + current trait list Output: Specific trait updates with reasoning

{
  "trait_updates": [
    {
      "trait_name": "shy",
      "action": "strengthen",
      "new_strength": 8,
      "description": "gets nervous in social interactions",
      "reasoning": "felt nervous talking shows social anxiety"
    }
  ]
}

3. Trait Updates Applied

• Create: New trait discovered from behavior
• Strengthen: Evidence reinforces existing trait (+1 strength)
• Weaken: Contradicting evidence reduces trait (-1 strength)

🎯 Design Principles

Conservative Analysis

• Avoid Over-Interpretation: Single events rarely create major traits
• Require Clear Evidence: Traits must be obviously demonstrated
• Skip Non-Behavioral: Physical descriptions don't create personality traits
• Focus on Patterns: Look for consistent behavioral indicators

Single-Word Traits

• Simplicity: Easy to understand and reference
• Clarity: Unambiguous personality descriptors
• Consistency: Standard vocabulary across characters
• Examples: shy, confident, romantic, studious, helpful, creative

Evidence-Based Development

• Every Change Justified: All trait updates have clear reasoning
• Observation-Driven: Traits emerge from actual experiences
• Gradual Evolution: Strength changes incrementally over time
• Realistic Growth: Matches how real personality develops

🎪 Trait Impact on Behavior

Behavioral Consistency

Characters with established traits should act accordingly:

• High Shy (8/10): Avoids eye contact, speaks quietly, gets nervous
• High Romantic (9/10): Focuses on attractive people, seeks connections
• High Studious (7/10): Prioritizes learning, discusses academic topics

Dynamic Responses

Traits influence how characters react to situations:

# Character with "shy" trait (strength 8)
response = "I looked down at my hands and mumbled quietly..."

# Character with "confident" trait (strength 9)  
response = "I smiled broadly and spoke up clearly..."

Trait Interactions

Multiple traits create complex, realistic personalities:

• Shy + Romantic: Wants connection but too nervous to approach
• Studious + Creative: Academic pursuits with artistic expression
• Helpful + Confident: Takes charge to assist others

📊 Trait Analytics

Personality Summaries

# Get dominant traits
strong_traits = character.get_active_traits(min_strength=7)
# Returns: {shy: 8/10, romantic: 9/10, studious: 7/10}

# Generate personality description  
summary = character.get_personality_summary()
# Returns: "shy (8/10), romantic (9/10), studious (7/10)"

Trait Evolution Tracking

• Strength Changes: Monitor how traits develop over time
• New Discoveries: Track when traits first emerge
• Behavioral Patterns: Observe consistency between traits and actions
• Character Growth: See personality evolution through experiences

🎯 Benefits

Realistic Development

• Gradual Change: Personality evolves naturally over time
• Experience-Driven: Traits emerge from actual interactions
• Individual Variation: Each character develops uniquely
• Authentic Growth: Matches real psychological development

Improved Roleplay

• Consistent Characters: Behavior matches established personality
• Dynamic Evolution: Characters grow and change realistically
• Rich Personalities: Complex trait combinations create depth
• Believable Responses: Actions align with developed traits

System Intelligence

• Automatic Development: No manual trait assignment needed
• Evidence-Based: Every trait justified by specific experiences
• Scalable Growth: Works across unlimited characters and interactions
• Self-Improving: Characters become more defined over time

This creates characters that feel genuinely alive and psychologically realistic, with personalities that develop naturally from their experiences and relationships.