From MarkItDown (175k stars, MIT) to curl_cffi (6k stars), a survey of 34 open-source tools for feeding data to AI. Categorized along five axes: whole-site crawling, AI browser agents, document conversion, smart extraction, and anti-detection infrastructure. The key to selection isn't which tool is best — it's scenario matching.
Uncle Bob's 4.18M-view post of 2026/7/23 isn't a manifesto — it's a reply to an engineer who started in 1983 asking whether needing to understand code psychologically makes him old-fashioned. And he doesn't skip the code entirely: his 6/1 four-stage pipeline post says 'I spot check the code,' with thresholds of crap ≤ 6 (convention is 30) and mutation runs that kill all survivors. Plus a breakdown of his open-sourced Acceptance-Pipeline-Specification and the three metric blind spots Grady Booch names.
The dominant paradigm in 3D generation in 2026 is video diffusion feeding feed-forward 3D reconstruction, and Lyra 2.0 is the flagship of that line. But three Best Papers at CVPR 2026 point at what comes next: SAM 3D brings foundation-model-scale object reconstruction, D4RT rebuilds dynamic 4D scenes in seconds from a unified transformer, and O-Voxel replaces Gaussians with structured latents. 3DGS still rules, but surface primitives are challenging it, and pixel-space diffusion is pushing back against latent space.
HeyGen's open-source HyperFrames defines video timelines with HTML data attributes, uses headless Chrome for frame-accurate seek-and-capture, then encodes via FFmpeg to MP4. 33k stars in 3 months, Apache 2.0, 21 agent skills — AI agents write HTML to produce video, no React needed.
Loop Engineering is the practice of designing systems that automatically prompt AI agents, rather than prompting them manually. Boris Cherny runs hundreds of agents, Addy Osmani coined the term, and Blake Crosley identified verification cost as the real bottleneck — this article covers primary sources, the five building blocks, applicability boundaries, and criticisms.
From the CLI tool kin3o to the CVPR 2026 paper OmniLottie — a survey of open-source approaches for converting text and images into Lottie animations, with performance benchmarks and selection guidance.
MUSE-Autoskill (2026) introduces a five-stage skill lifecycle framework. Self-created skills achieve 60.35% (+7.16%) on SkillsBench overall, and an impressive 87.94% on tasks where skill generation succeeds — surpassing the human-authored skill ceiling. This post synthesizes six arXiv papers to map the full landscape of skill evolution research.
Even with temperature=0, LLM outputs can still fluctuate by up to 15% in practice. To rigorously compare agent changes, you need a frozen golden set, at least 3 runs per query averaged out, LLM-as-judge blind evaluation (pairwise preference flip rate reaches 35%), and paired statistical tests -- not just running each version once and going by feel.
The industry has converged on using OpenTelemetry GenAI semantic conventions to turn every LLM call and tool call into a span. Detecting the three major failure modes then splits into three tracks: faithfulness + semantic entropy for hallucinations, framework-level symbolic guardrails for tool misuse, and max steps + action hash deduplication for infinite loops — all wired into a Final / Trajectory / Single-step three-layer evaluation framework.
Agent decision-making under resource constraints is bounded rationality reborn: Rational Metareasoning uses VOC rewards to save 20-37% of tokens, BATS proves that adding budget without budget awareness is futile, FrugalGPT cascades cut costs by up to 98%, and Speculative Actions reduce latency by 20%. The three constraints ultimately converge into a single Pareto curve, and the overarching trend is moving from humans tuning knobs to models making resource-rational decisions on their own.
Three seemingly distinct agent security problems — tool output injection, trust boundaries, malicious agents — share the same root cause: LLMs flatten instructions and data into a single token stream, making them architecturally unable to distinguish between the two. Understand this through-line and you can trace every attack from EchoLeak (CVE-2025-32711, zero-click) to the Morris II AI worm, and see why 'making the model behave' doesn't work — only architectural constraints (six design patterns, CaMeL) do.
Traditional RAG is a fixed pipeline of 'retrieve then answer.' Agentic RAG splits retrieval into three decision layers: when to retrieve (FLARE uses token probabilities; Adaptive-RAG uses a complexity classifier), what to retrieve (HyDE / RAG-Fusion / decomposition / Step-back), and how to fuse (RRF k=60 then cross-encoder rerank then compression -- Anthropic measured a -67% failure rate reduction). Key counter-intuitive insight: unnecessary retrieval hurts quality -- 'deciding not to retrieve' is a first-class capability.
Automatic prompt optimization (APO) has evolved from APE/OPRO to GEPA: replacing sparse rewards with linguistic reflection, winning over GRPO by ~6pp with 4-35x fewer rollouts. Meanwhile, tool descriptions are the overlooked prompt -- small wording changes can shift tool selection rates by 10x, and Anthropic's experiments show Claude self-rewriting tool descriptions outperforms human experts. These two lines are converging: eval-driven automatic optimization is eating hand-tuned prompts.
An autonomous research agent = four controllable stages: planning (decompose into sub-questions), retrieval loop (search -> read -> reflect on gaps -> search again), evidence arbitration (>=2 independent sources, typed conflict handling), and verifiable output (sentence-level citations + independent verification pass). Two approaches: training-based uses RL to learn end-to-end when to search (Search-R1 +41%); orchestration-based uses orchestrator-worker division of labor (Anthropic internal eval +90.2%, at ~15x token cost).
Inferring another's beliefs/goals/intentions from observed behavior is called Machine Theory of Mind. Three lineages: symbolic BDI, Bayesian inverse planning, and deep learning ToMnet. The biggest controversy in the LLM era is that GPT-4 still trails humans by >10 points on ToMBench — are high scores genuine reasoning or statistical shortcuts?
At 99% accuracy per step over 100 steps, the error-free completion rate drops to just 36% -- error compounding is a structural problem, not something prompt tuning can fix. Distributed systems' supervisor trees, bulkheads, circuit breakers, sagas, and durable execution can be mapped almost one-to-one into agent orchestration. But LLMs introduce a failure class that traditional systems never had -- semantic errors that don't crash -- which require Inspector agents (recovering 96.4%) and redundancy voting (MAKER: one million steps with zero errors) to address.
Cosine similarity and relevance systematically diverge across an entire class of scenarios: negation (most IR models score at or below random on NevIR), exact identifiers, numeric thresholds, and logical combinations (SoTA models achieve recall@100 < 20 on LIMIT) -- some of these hit the theoretical ceiling of the single-vector paradigm, and switching to a larger model will not help. Recommended remedy order: hybrid BM25 -> reranker (Anthropic measured -67%) -> upstream metadata routing -> domain fine-tuning / multi-vector.
As tools scale up, selection accuracy doesn't degrade gracefully — it collapses: 4 to 51 tools drops from 43% to 2%, 10 to 100+ drops from 78% to 13.62%. The root fix is to stop stuffing everything in at once — Anthropic's Tool Search Tool uses defer loading plus retrieval to cut 85% of tokens, pushing Opus 4.5 accuracy from 79.5% to 88.1%. Description quality has conditional payoff: negligible in simple scenarios, but correctness jumps from 44% to 50% in multi-tool chaining.
Traditional Chinese RAG retrieval failures are a three-layer stack: embedding granularity defects (BGE/GTE from 0.1B to 7B all mis-rank on simple queries like 'fried chicken'), Simplified Chinese / English corpus dominance causing local vocabulary drift ('premium', 'exclusion clause' alignment is unreliable), and MTEB Chinese benchmarks being Simplified Chinese making model selection signals misleading. The fix is architectural: OpenCC normalization -> hybrid + jieba segmentation -> reranker -> local fine-tuning last -- and the prerequisite for all of it is building a Traditional Chinese eval set first.
Making 'chunk and embed every uploaded file automatically' the default behavior means making a decision for the LLM that it could have made itself. From Self-RAG (2310.11511) and Adaptive-RAG (2403.14403) to AgenticOCR (2602.24134), the academic trajectory is pushing three layers of decision-making -- whether to retrieve, whether to parse, and how to chunk -- from the ingestion pipeline back to the agent at conversation time.