Instead of training ever-bigger AI, could you just give a smaller one good tools, memory, and skills?
Can externalized memory and skills replace model scaling?
This explores whether moving knowledge, memory, and know-how out of a model's weights (into tools, state caches, and separate memory systems) can do the job we'd otherwise buy with more parameters.
This explores whether moving knowledge, memory, and know-how out of a model's weights (into tools, state caches, and separate memory systems) can do the job we'd otherwise buy with more parameters. For facts, the corpus says yes, and there's a proof behind it. Can models store unlimited facts without growing larger? shows that what a model can memorize in its weights is capped by its size. A model that can call a tool can recall an unbounded number of facts through a simple circuit. Cramming facts in by fine-tuning also degrades general ability, because it overwrites prior knowledge. Buying a bigger model is the wrong way to make a model know more.
The same move works beyond simple lookup. Can external state caches let models solve harder problems? organizes state in four levels: weights, context, a persistent REPL with subagents, and disk-backed history. A fixed model can then read and write memory well beyond its instruction stream, and the authors report gains on ARC-AGI-3. The catch is that individual components weren't ablated, so we don't know which layer does the work. Can a separate memory model inject knowledge without touching the LLM? goes further. A dedicated memory model absorbs new knowledge, so a frozen proprietary model never gets retrained and inference cost stops growing with corpus size. You pay for it in up-front training and limited capacity.
The limits show up when the problem is reasoning rather than remembering. Can non-reasoning models catch up with more compute? finds that non-reasoning models never catch reasoning models, however much inference compute they get. Training instills a protocol that makes extra tokens productive, and no amount of external support substitutes for that. Do larger language models solve constrained optimization better? finds LLMs stuck at roughly 55–60% constraint satisfaction regardless of size or training regime. Scale doesn't fix that, but that note doesn't test whether external scaffolding would.
The field is also split on whether memory should live outside the model at all. Should agent memory live inside the model backbone? argues that external memory and the backbone optimize independently and end up failing to coordinate. It puts memory inside the backbone so the whole thing trains end to end. Can neural memory modules scale language models beyond attention limits? takes a middle path. A memory module built into the architecture stores surprising tokens and reaches 2M+ token contexts without quadratic cost.
The sharper reframing is that scaling isn't one dial. Depth over width helps small models (Does depth matter more than width for tiny language models?), and looping the same layers beats bigger feedforward networks on reasoning (Can models learn by looping instead of growing larger?). A 3B looped model can match explicit chain-of-thought (Can latent reasoning close the scaling gap with explicit chain-of-thought?), and latent thought vectors add a scaling axis independent of parameters (Can latent thought vectors scale language models beyond parameters?). Skill can also be moved by training rather than size: Can small models match large models on function calling? shows small models matching large ones on function calling after learning from a teacher's good and bad examples. So externalization can replace parameter count for knowledge. For skill, what replaces size is better training and architecture. The corpus has little direct evidence that external skill libraries stand in for a stronger model.
Sources 12 notes
A formal proof and experiments show in-weight memorization is bounded by model size, while tool-use enables unbounded factual recall through a simple circuit. In-weight finetuning also degrades general capability by overwriting prior knowledge.
Prime Agent organizes persistent state in four levels (weights, context, persistent REPL plus subagents, disk-backed history) to let models read and write addressable state beyond their instruction stream. The approach isolates harness failures from model failures and reported gains on ARC-AGI-3, though specific components remain unablated.
MeMo trains a dedicated memory model to encode new knowledge, eliminating inference-time search costs that scale with corpus size. It avoids fine-tuning risks and works with frozen proprietary models, but trades this for up-front training cost and capacity limits.
Reasoning models persistently outperform non-reasoning models regardless of inference budget because training instills a reasoning protocol that makes additional tokens productive. The gap is fundamentally about deployment mechanisms and training structure, not raw capability.
Across constrained-optimization tasks, LLMs converge to ~55–60% constraint satisfaction independent of architecture, parameter count, or training regime. Reasoning models do not systematically outperform standard models, suggesting a fundamental ceiling rather than a scaling gap.
Show all 12 sources
Metis demonstrates that agent memory can be implemented as a persistent state and autonomous procedures within the model backbone rather than external modules. This approach enables end-to-end training and avoids the decoupling failures where external memory and backbone optimize independently.
Titans architecture separates attention (short-term, quadratic) from neural memory (long-term, compressed), prioritizing surprising tokens for storage. The model outperforms standard Transformers and linear RNNs across tasks while scaling to 2M+ token contexts without quadratic penalties.
MobileLLM shows deep-and-thin architectures yield 2.7–4.3% accuracy gains over balanced designs at 125M–350M scale by composing abstract concepts through layers rather than spreading parameters across width.
Models that re-apply layers in recurrent depth outperform larger feedforward networks on reasoning tasks. This works because recursion enables state tracking and compositional generalization that parameter scaling alone cannot achieve, with convergence signals providing natural halting.
LOTUS, a looped Transformer trained with gold CoT supervision at each latent position, closes the latent-to-explicit gap on GSM8K and cuts thought-phase latency by 2.5× to 6.9×. Latent reasoning need not be verbalized token-by-token to remain legible and competitive.
Latent-Thought Language Models achieve superior sample and parameter efficiency by coupling fast local variational learning with slow global decoder learning. This dual-rate scheme scales few-shot reasoning across both model and latent size, creating independent scaling dimensions beyond traditional parameter scaling.
Small models fine-tuned via DPO on correct and incorrect function-calling examples from a large teacher model achieve high accuracy on logical and mathematical tasks. DPO's explicit negative examples directly target the rigid output format failures where SFT alone underperforms.
Papers this line draws on 8
The research behind the notes this line reads — ranked by how closely each paper relates.
- Scaling up Test-Time Compute with Latent Reasoning: A Recurrent Depth Approach
- Know It, Act on It: Investigating Memory Utilization in LLM Personalization
- Provable Benefits of In-Tool Learning for Large Language Models
- Hierarchical Reasoning Model
- ZebraLogic: On the Scaling Limits of LLMs for Logical Reasoning
- Metis: Memory Foundation Model
- SoftCoT: Soft Chain-of-Thought for Efficient Reasoning with LLMs
- Memorization and Knowledge Injection in Gated LLMs