AI Papers of the Week
Every paper worth reading in AI, hand-picked one week at a time.

xMemory
xMemory argues that standard RAG retrieval is a poor fit for agent memory because the evidence source is a bounded, coherent dialogue stream where candidate spans are highly correlated near-duplicates. Fixed top-k similarity retrieval collapses into a single dense region, returning redundant context, while post-hoc pruning can break temporally linked evidence chains. xMemory replaces this with hierarchical memory construction and structure-aware top-down retrieval.

SALE
This paper from Meta shows that small agents match large ones on simple tasks but fall sharply behind as complexity grows, with the cheapest agent reaching only about 21% of the largest agent’s accuracy on the hardest problems. To address this, the authors introduce SALE (Strategy Auctions for Workload Efficiency), a marketplace-inspired framework where heterogeneous agents bid with strategic plans, are scored on cost-value trade-offs, and refine their bids using shared auction memory.

InfMem
InfMem is a cognitive agent for ultra-long document QA that uses System-2-style control to actively manage bounded memory. Instead of passively compressing each chunk as it streams in, InfMem runs a PreThink-Retrieve-Write loop that monitors evidence sufficiency, fetches missing facts from anywhere in the document, and compresses everything into a fixed-size memory - then stops early once it has enough.

Agent Primitives
Agent Primitives introduces reusable latent building blocks for LLM-based multi-agent systems. Inspired by how neural networks are built from composable modules like residual blocks and attention heads, the authors decompose existing MAS architectures into three recurring computation patterns that communicate via KV cache instead of natural language, reducing error accumulation and boosting efficiency.

Heterogeneous Computing for AI Agent Inference
This paper introduces Operational Intensity (OI) and Capacity Footprint (CF) as two metrics that better characterize AI agent inference workloads than traditional roofline models, revealing that memory capacity - not just bandwidth or compute - is often the true bottleneck. Analysis across agent types (chatbot, coding, web-use, computer-use) shows that agentic workflows create vastly different and rapidly growing demands on hardware, with context lengths snowballing to over 1M tokens in coding agents. The authors argue for disaggregated, heterogeneous compute architectures with specialized prefill and decode accelerators, hardware-aware model co-design, and large-capacity memory disaggregation as essential directions for scaling AI agent systems.

VibeTensor
VibeTensor is an open-source deep learning system software stack from NVLabs that was fully generated by LLM-powered coding agents under high-level human guidance. The system implements a PyTorch-style eager tensor library with a C++20/CUDA core, Python and Node.js frontends, its own autograd engine, CUDA runtime, and caching allocator - demonstrating that coding agents can produce coherent system software spanning language bindings down to GPU memory management.

LingBot-World: Open-Source World Simulator
LingBot-World is an open-source world simulator that evolves a video generation model into an interactive, real-time environment engine. Built on a 28B-parameter Mixture-of-Experts architecture, it achieves high-fidelity dynamics across diverse domains with sub-second latency at 16 fps, outperforming Genie 3 and Mirage 2 in dynamic degree while being fully open-source.

Team of Rivals: Orchestrating Reliable AI Agents
This paper proposes organizing AI agents into corporate-style teams with strict role boundaries and opposing incentives (planners, executors, critics, experts) to achieve reliability through careful orchestration of imperfect components. A remote code executor separates reasoning from data transformations, preventing raw tool outputs from contaminating agent context windows. The system achieves over 90% internal error interception before user exposure while maintaining acceptable latency tradeoffs.

Memory Control for Long-Horizon Agents
This paper introduces the Agent Cognitive Compressor (ACC), a bio-inspired mechanism that addresses degraded agent behavior in long multi-turn workflows caused by loss of constraint focus, error accumulation, and memory-induced drift. ACC replaces continuous transcript retention with a bounded internal state that updates incrementally during each interaction turn.

Rethinking Multi-Agent Workflows
This paper challenges the assumption that complex tasks require multiple specialized AI agents, demonstrating that a single LLM agent, through iterative dialogue, can match the performance of homogeneous multi-agent workflows while gaining efficiency from KV cache reuse.

Efficient Agents
A comprehensive review examining how to make LLM-based agents more efficient for real-world deployment, focusing on three core components: memory (bounding context via compression), tool learning (RL strategies to minimize tool invocation), and planning (controlled search mechanisms). The paper characterizes efficiency through dual metrics and Pareto frontier analysis between effectiveness and cost.

Extending Context by Dropping Positional Embeddings
DroPE introduces a method for extending a language model’s context window after pretraining without expensive long-context fine-tuning. The approach involves removing positional embeddings from a pretrained model and performing brief recalibration at the original context length.

Unified Long-Term and Short-Term Memory for LLM Agents
AgeMem introduces a unified framework that integrates both long-term and short-term memory operations into an LLM agent’s decision-making policy. The system enables agents to autonomously determine what and when to store, retrieve, update, summarize, or discard information by exposing memory operations as tool-based actions.

Active Context Compression for LLM Agents
Focus introduces an agent-centered architecture that enables LLM agents to autonomously manage their own memory by deciding when to consolidate learnings into a persistent “Knowledge” block and actively prune raw interaction history. The design is inspired by the biological navigation patterns of Physarum polycephalum (slime mold).

Agent-as-a-Judge
This comprehensive survey traces the evolution from LLM-based evaluation to agentic evaluation approaches, establishing the first taxonomy for this paradigm shift. As evaluation tasks grow more intricate and specialized, traditional single-pass language model judges become insufficient.

Efficient Lifelong Memory for LLM Agents
SimpleMem introduces a memory framework built on semantic lossless compression that addresses the tension between maintaining comprehensive long-term memory and minimizing token overhead for LLM agents. The approach achieves a 26.4% F1 improvement over baselines while reducing token consumption by up to 30-fold during inference.

Ministral 3
Mistral AI releases Ministral 3, a family of compact language models (3B, 8B, 14B parameters) designed for compute and memory-constrained applications from mobile to edge deployments. Created through Cascade Distillation (iterative pruning with continued training), each size offers pretrained, instruction-finetuned, and reasoning variants with integrated image understanding, released under Apache 2.0.

MemRL
MemRL enables LLM agents to improve continuously without retraining by separating a frozen model’s reasoning from an evolving memory system. A Two-Phase Retrieval mechanism filters candidates by semantic relevance, then ranks them using learned Q-values that improve through trial-and-error, outperforming existing methods on HLE, BigCodeBench, ALFWorld, and Lifelong Agent Bench.

Recursive Language Models
Recursive Language Models (RLMs) are a general inference strategy that allows LLMs to process arbitrarily long prompts by treating them as part of an external environment. Rather than feeding long contexts directly into the model, RLMs load the prompt as a variable in a Python REPL and let the LLM programmatically examine, decompose, and recursively call itself over snippets.

Adversarial Program Evolution with LLMs
Digital Red Queen (DRQ) introduces an algorithm where LLMs evolve assembly-like programs called “warriors” that compete for control of a virtual machine in the game of Core War. Rather than optimizing toward static objectives, DRQ embraces “Red Queen” dynamics where goals continually shift based on competition, demonstrating how adversarial self-play can drive the evolution of increasingly sophisticated programs.

Confucius Code Agent
Confucius Code Agent (CCA) is a software engineering agent designed to operate on large-scale codebases. Built on the Confucius SDK, it introduces a three-axis design philosophy separating Agent Experience (AX), User Experience (UX), and Developer Experience (DX) to enable robust multi-step reasoning and modular tool use.

End-to-End Test-Time Training for Long Context
This paper reframes long-context language modeling as a continual learning problem rather than architecture design. TTT-E2E uses a standard Transformer with sliding-window attention that continues learning at test time via next-token prediction, compressing context into its weights rather than storing all key-value pairs.

Geometric Memory in Sequence Models
This paper identifies a dramatically different form of how deep sequence models store factual information called geometric memory, contrasting with the traditional associative memory view. Models synthesize embeddings encoding global relationships between all entities, even ones that never co-occur in training.

Manifold-Constrained Hyper-Connections
This DeepSeek paper proposes Manifold-Constrained Hyper-Connections (mHC), a framework that extends residual connections by expanding residual stream width while restoring training stability. The key insight: unconstrained Hyper-Connections compromise identity mapping, causing training instability at scale.