Key points of Multi Stream Attention

They had a point, I'm sure it's buried in here somewhere.

The general rule

Using technical jargon might make your abstract shorter - but it’ll take twice as long to read. Start the paper (abstract, intro) giving the readers some context on the problem you are trying to solve and on what is the state of solutions today, and USE VISUALIZATIONS.

Relevant XKCD: xkcd #2501, Average Familiarity by Randall Munroe (CC BY-NC 2.5).

Reading the abstract, a reader with no sufficient context on the innovations in the field (like myself) will be lost quickly (after being attacked by “content-dependent retrieval” and “single-stream softmax attention” in the first sentence, and the first architecture figure in page 7).

After doing some catching up, I think the main points of the paper could be described like so:

1. Residual streams could be upgraded to be non-uniform with attention

This is not a new contribution by the paper, but it is the main important context I was missing, and it’s one of the more interesting things I learned going over this paper. The credit for this idea (as far as I could tell) goes to Attention Residuals (AttnRes) (Kimi Team, 2026), which builds on earlier ways of letting a layer read all previous layers directly (Huang et al., 2017; Pagliardini et al., 2024; Xiao et al., 2025).

2. Attention over both depth AND tokens (/time)

A previous architecture - AttnRes - used attention on the residual stream of this same token. In this paper they expand this to both look across the different network layers as well as across each layer’s reaction to the previous tokens (here - up to 12 previous tokens). Another expansion of this idea is the use of multi-headed attention here. In this paper they use the convolution over the token history as the way to combine these. Here as well the idea isn’t novel (Mixture-of-Depths Attention attends over both tokens and earlier layers (Zhu et al., 2026), and short convolutions over previous tokens appear in Primer and Canon layers (So et al., 2021; Allen-Zhu, 2025)), but the use of convolutions for inter-token mixing in the depth attention is new as far as I could tell.

Figure 2c of the paper (CC BY 4.0): Block MSAR.

3. We made it work properly on production-sized models

Maybe the biggest contribution of the paper, in my view, is showing how they combined the first two points and using clever parametrization and caching they made it work on a large scale model, showing improvements over both vanilla architecture and previous attempts that scale to large models (not the biggest, but 18B and 28B are respectable models and not a model organism (even though this is the MoE total parameter count, not active)). Caveat that should be stated here - this is a properly sized model but the compute budget for training is much much smaller than that of a “proper” production size LLM.

How they could have done better

Maybe the paper isn’t aimed at outsiders, but as one trying to read it - bringing me “up to speed” wouldn’t have taken more than a few lines, written in simple english, and creating a more in depth view of their architectural suggestion (i.e figure 2, with a bit more focus on the architectural changes and most importantly - much earlier in the paper). Additionally, I thing the framing of attention over both depth (of the network) and over previous tokens jointly is more helpful (at least to me).

The main contribution of this paper are it’s results, which the paper presents in a very forward manner (abstract, first figure). They would be easier to understand given the context of the architectural changes.

References

  1. Attention Residuals
    Kimi Team
    arXiv preprint arXiv:2603.15031, 2026
  2. Densely Connected Convolutional Networks
    Gao Huang, Zhuang Liu, Laurens Maaten, and 1 more author
    In Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, 2017
  3. DenseFormer: Enhancing Information Flow in Transformers via Depth Weighted Averaging
    Matteo Pagliardini, Amirkeivan Mohtashami, François Fleuret, and 1 more author
    In Advances in Neural Information Processing Systems, 2024
  4. MUDDFormer: Breaking Residual Bottlenecks in Transformers via Multiway Dynamic Dense Connections
    Da Xiao, Qingye Meng, Shengping Li, and 1 more author
    arXiv preprint arXiv:2502.12170, 2025
  5. Mixture-of-Depths Attention
    Lianghui Zhu, Yuxin Fang, Bencheng Liao, and 8 more authors
    arXiv preprint arXiv:2603.15619, 2026
  6. Primer: Searching for Efficient Transformers for Language Modeling
    David R. So, Wojciech Mańke, Hanxiao Liu, and 3 more authors
    In Advances in Neural Information Processing Systems, 2021
  7. Physics of Language Models: Part 4.1, Architecture Design and the Magic of Canon Layers
    Zeyuan Allen-Zhu
    In Advances in Neural Information Processing Systems, 2025
    arXiv:2512.17351



Enjoy Reading This Article?

Here are some more articles you might like to read next:

  • The Illustrated Speculative Decoder
  • Critique of of Multi-Stream Attention Residuals
  • explaing HC and mHC
  • Making the MSAR methods section easier to follow
  • Critique of Multi-Stream Attention Residuals