Memory in the Age of AI Agents: A Survey
1.1 LLM-based Agent Systems
1.2 Agent Memory Systems
1.3 Comparing Agent Memory with Other Key Concepts
1.3.1 Agent Memory vs. LLM Memory
1.3.2 Agent Memory vs. RAG
1.3.3 Agent Memory vs. Context Engineering
2.1 Token-level Memory
2.1.1 Flat Memory (1D)
2.1.2 Planar Memory (2D)
2.1.3 Hierarchical Memory (3D)
2.2 Parametric Memory
2.2.1 Internal Parametric Memory
2.2.2 External Parametric Memory
2.3 Latent Memory
2.3.1 Generate
2.3.2 Reuse
2.4 Adaptation
3. Functions: Why Agents Need Memory?
3.1 Factual Memory
3.1.1 User factual memory
3.1.2 Environment factual memory
3.2 Experiential Memory
3.2.1 Case-based Memory
3.2.2 Strategy-based Memory
3.2.3 Skill-based Memory
3.2.4 Hybrid memory
3.3 Working Memory
3.3.1 Single-turn Working Memory
3.3.2 Multi-turn Working Memory
4. Dynamics: How Memory Operates and Evolves?
4.1.1 Semantic Summarization
4.1.2 Knowledge Distillation
4.1.3 Structured Construction
4.1.4 Latent Representation
4.1.5 Parametric Internalization
4.2 Memory Evolution
4.2.1 Consolidation
4.2.2 Updating
4.2.3 Forgetting
4.3 Memory Retrieval
4.3.1 Retrieval Timing and Intent
4.3.2 Query Construction
4.3.3 Retrieval Strategies
4.3.4 Post-Retrieval Processing
5. Resources and Frameworks
5.1 Benchmarks and Datasets
5.1.1 Benchmarks for Memory / Lifelong / Self-Evolving Agents
5.2 Open-Source Frameworks
6. Positions and Frontiers
6.1 Memory Retrieval vs. Memory Generation
6.1.1 Look Back: From Memory Retrieval to Memory Generation
6.1.2 Future Perspective
6.2 Automated Memory Management
6.2.1 Look-Back: From Hand-crafted to Automatically Constructed Memory Systems.
6.2.2 Future Perspective
6.3 Reinforcement Learning Meets Agent Memory
6.3.1 Look-Back: RL is Internalizing Memory Management Abilities for Agents.
6.3.2 Future Perspective
6.4 Multimodal Memory
6.4.1 Look-Back
6.4.2 Future Perspective
6.5 Shared Memory in Multi-Agent Systems
6.5.1 Look-Back: From Isolated Memories to Shared Cognitive Substrates
6.5.2 Future Perspective
6.6 Memory for World Model
6.6.1 Look-Back
6.6.2 Future Perspective
6.7 Trustworthy Memory
6.7.1 Look-Back: From Trustworthy RAG to Trustworthy Memory
6.7.2 Future Perspective
6.8 Human-Cognitive Connections
6.8.1 Look Back
6.8.2 Future Perspective
