[AAAI 2026 Oral] MOTIF: Multi-strategy Optimization via Turn-based Interactive Framework

July 7, 2026 ยท View on GitHub

arXiv Python License

A competitive multi-agent framework that evolves combinatorial optimization strategies through LLM-powered turn-based interactions.


๐Ÿ“ฐ 1. News

DateUpdate
๐ŸŽ‰ Dec. 2025Refactored codebase for better modularity and extensibility
๐Ÿ† Nov. 2025Paper accepted for oral presentation at AAAI 2026!
๐Ÿš€ Aug. 2025Released first version of MOTIF

๐Ÿ” 2. Overview

MOTIF is a turn-based, multi-agent framework for improving combinatorial optimization solvers by jointly evolving multiple algorithmic strategies rather than tuning a single heuristic.

MOTIF Overview

Key Features

  • ๐ŸŽฎ Competitive-Collaborative Learning: Two LLM agents take alternating turns to refine components
  • ๐Ÿ“Š Dynamic Baselines: Performance guided by adaptive baseline comparisons
  • ๐Ÿ”„ Opponent Feedback: Each agent learns from the other's improvements
  • ๐Ÿงฉ Structured Operators: Modular prompts enable targeted strategy refinement
  • ๐ŸŒ Broad Search Space: Competitive dynamics encourage diverse adaptations

๐Ÿš€ 3. Quick Start

Step 1. Set Up Environment Variables

Create a .env file in the project root:

OPENAI_API_KEY="your-openai-api-key-here"

Step 2. Install Dependencies

pip install -r requirements.txt

Step 3. Run Default Experiment

python main.py

Step 4. Run Custom Experiments

Specify a solver:

python main.py solver=tsp_aco
python main.py solver=cvrp_dr_f1_f2_f3

Configure MCTS parameters:

python main.py \
       solver=tsp_aco \
       mcts.outer_iterations=20 \
       mcts.inner_iterations=10 \
       mcts.final_iterations=10

Customize LLM settings:

python main.py \
       llm.model=gpt-4o \
       llm.temperature=0.8

Step 5. Results

Results are saved to ./results/:

  • F*_final_best.py: Final optimized strategy implementations
  • *_round_*.json: Detailed experiment logs with performance metrics

๐Ÿ“‹ 4. Supported Problems and Solvers

SolverProblemsStrategies
ACOTSP, CVRP, MKP- F1: Heuristic & Pheromone Initialization
- F2: Probabilistic Transition Rule
- F3: Pheromone Update Rule
ACOOP, BPP- F1: Heuristic & Pheromone Initialization
- F2: Pheromone Update Rule
GLSTSP- F1: Guide Matrix Initialization
DRTSP, CVRP, BPP- F1: Initial Solution Construction Rule
- F2: Deconstruction Rule
- F3: Repair Rule

๐Ÿ”ง 5. Customization and Extension

MOTIF is designed for easy extension. Follow these guides to add new problems and solvers.

Step 1. Create the problem directory:

problems/
โ””โ”€โ”€ problem_solver/
    โ”œโ”€โ”€ __init__.py
	โ”œโ”€โ”€ solver.py        # Solver implementation
	โ”œโ”€โ”€ eval.py          # Evaluation functions
	โ”œโ”€โ”€ generator.py     # Instance generator
	โ”œโ”€โ”€ prompts.py       # LLM prompts for each strategy
	โ”œโ”€โ”€ F1.py            # Strategy component 1 (baseline)
	โ”œโ”€โ”€ F2.py            # Strategy component 2 (baseline)
	โ”œโ”€โ”€ F3.py            # Strategy component 3 (baseline)
	โ””โ”€โ”€ datasets/        # Training and test datasets

Step 2. Implement core files:

  • prompts.py: Define PROBLEM_DESCRIPTION, CONSTRAINTS, and strategy prompts (F1, F2, F3)
  • F*.py: Provide baseline implementations for each strategy component

Step 3. Create solver configuration:

# @package _global_.solver
base_path: ${paths.problems_dir}/problem_solver # Path to problem-solver directory

functions: [F1, F2] # Strategy files to optimize

๐Ÿ“š 6. Citation

If you find MOTIF useful in your research, please consider citing our paper:

@inproceedings{nguyen2026motif,
  title     = {MOTIF: Multi-Strategy Optimization via Turn-based Interactive Framework},
  author    = {Kiet, Nguyen Viet Tuan and Tung, Dao Van and Dao, Tran Cong and Binh, Huynh Thi Thanh},
  booktitle = {Proceedings of the AAAI Conference on Artificial Intelligence (AAAI)},
  year      = {2026},
  address   = {Singapore},
  month     = {January},
  note      = {Oral Presentation}
}

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