
MemOS is an operating system for Large Language Models (LLMs) that enhances them with long-term memory capabilities. It allows LLMs to store, retrieve, and manage information, enabling more context-aware, consistent, and personalized interactions.
- Website: https://memos.openmem.net/
- Documentation: https://memos.openmem.net/docs/home
- API Reference: https://memos.openmem.net/docs/api/info
- Source Code: https://github.com/MemTensor/MemOS
MemOS demonstrates significant improvements over baseline memory solutions in multiple reasoning tasks.
Model | Avg. Score | Multi-Hop | Open Domain | Single-Hop | Temporal Reasoning |
---|---|---|---|---|---|
OpenAI | 0.5275 | 0.6028 | 0.3299 | 0.6183 | 0.2825 |
MemOS | 0.7331 | 0.6430 | 0.5521 | 0.7844 | 0.7321 |
Improvement | +38.98% | +6.67% | +67.35% | +26.86% | +159.15% |
💡 Temporal reasoning accuracy improved by 159% compared to the OpenAI baseline.
Note
Comparison of LLM Judge Scores across five major tasks in the LOCOMO benchmark. Each bar shows the mean evaluation score judged by LLMs for a given method-task pair, with standard deviation as error bars. MemOS-0630 consistently outperforms baseline methods (LangMem, Zep, OpenAI, Mem0) across all task types, especially in multi-hop and temporal reasoning scenarios.

- 🧠 Memory-Augmented Generation (MAG): Provides a unified API for memory operations, integrating with LLMs to enhance chat and reasoning with contextual memory retrieval.
- 📦 Modular Memory Architecture (MemCube): A flexible and modular architecture that allows for easy integration and management of different memory types.
- 💾 Multiple Memory Types:
- Textual Memory: For storing and retrieving unstructured or structured text knowledge.
- Activation Memory: Caches key-value pairs (
KVCacheMemory
) to accelerate LLM inference and context reuse. - Parametric Memory: Stores model adaptation parameters (e.g., LoRA weights).
- 🔌 Extensible: Easily extend and customize memory modules, data sources, and LLM integrations.
Here's a quick example of how to create a MemCube
, load it from a directory, access its memories, and save it.
from memos.mem_cube.general import GeneralMemCube
# Initialize a MemCube from a local directory
mem_cube = GeneralMemCube.init_from_dir("examples/data/mem_cube_2")
# Access and print all memories
print("--- Textual Memories ---")
for item in mem_cube.text_mem.get_all():
print(item)
print("\n--- Activation Memories ---")
for item in mem_cube.act_mem.get_all():
print(item)
# Save the MemCube to a new directory
mem_cube.dump("tmp/mem_cube")
What about MOS
(Memory Operating System)? It's a higher-level orchestration layer that manages multiple MemCubes and provides a unified API for memory operations. Here's a quick example of how to use MOS:
from memos.configs.mem_os import MOSConfig
from memos.mem_os.main import MOS
# init MOS
mos_config = MOSConfig.from_json_file("examples/data/config/simple_memos_config.json")
memory = MOS(mos_config)
# create user
user_id = "b41a34d5-5cae-4b46-8c49-d03794d206f5"
memory.create_user(user_id=user_id)
# register cube for user
memory.register_mem_cube("examples/data/mem_cube_2", user_id=user_id)
# add memory for user
memory.add(
messages=[
{"role": "user", "content": "I like playing football."},
{"role": "assistant", "content": "I like playing football too."},
],
user_id=user_id,
)
# Later, when you want to retrieve memory for user
retrieved_memories = memory.search(query="What do you like?", user_id=user_id)
# output text_memories: I like playing football, act_memories, para_memories
print(f"text_memories: {retrieved_memories['text_mem']}")
For more detailed examples, please check out the examples
directory.
Warning
Currently, MemOS primarily supports Linux platforms. You may encounter issues on Windows and macOS temporarily.
pip install MemoryOS
To contribute to MemOS, clone the repository and install it in editable mode:
git clone https://github.com/MemTensor/MemOS.git
cd MemOS
make install
To use MemOS with Ollama, first install the Ollama CLI:
curl -fsSL https://ollama.com/install.sh | sh
To use functionalities based on the transformers
library, ensure you have PyTorch installed (CUDA version recommended for GPU acceleration).
Join our community to ask questions, share your projects, and connect with other developers.
- GitHub Issues: Report bugs or request features in our GitHub Issues.
- GitHub Pull Requests: Contribute code improvements via Pull Requests.
- GitHub Discussions: Participate in our GitHub Discussions to ask questions or share ideas.
- Discord: Join our Discord Server.
- WeChat: Scan the QR code to join our WeChat group.
If you use MemOS in your research, please cite our paper:
@article{li2025memos,
title={MemOS: An Operating System for Memory-Augmented Generation (MAG) in Large Language Models},
author={Li, Zhiyu and Song, Shichao and Wang, Hanyu and Niu, Simin and Chen, Ding and Yang, Jiawei and Xi, Chenyang and Lai, Huayi and Zhao, Jihao and Wang, Yezhaohui and others},
journal={arXiv preprint arXiv:2505.22101},
year={2025}
}
We welcome contributions from the community! Please read our contribution guidelines to get started.
MemOS is licensed under the Apache 2.0 License.
Stay up to date with the latest MemOS announcements, releases, and community highlights.
- 2025-07-07 – 🎉 MemOS 1.0 (Stellar) Preview Release: A SOTA Memory OS for LLMs is now open-sourced.
- 2025-05-28 – 🎉 Short Paper Uploaded: MemOS: An Operating System for Memory-Augmented Generation (MAG) in Large Language Models was published on arXiv.
- 2024-07-04 – 🎉 Memory3 Model Released at WAIC 2024: The new memory-layered architecture model was unveiled at the 2024 World Artificial Intelligence Conference.
- 2024-07-01 – 🎉 Memory3 Paper Released: Memory3: Language Modeling with Explicit Memory introduces the new approach to structured memory in LLMs.