CrewAI (GitHub 57.4k stars, MIT, PyPI 11.6M weekly downloads) defines agents by role, goal, and backstory, then groups them into crews for collaboration. Unlike LangGraph's graph-first and MAF's workflow-first approach, CrewAI is team-first — you don't draw nodes and edges, you describe who's on the team and what each person does. It fully removed its LangChain dependency in late 2024 and is now a standalone framework. The commercial side splits into the open-source package and AMP, a managed platform adding visual building, deployment, tracing, and compliance.
Exa turns every indexed web page into an embedding and retrieves by vector similarity instead of keyword matching. Official pricing as checked on 2026-08-21: $7 / 1k requests for /search (first 10 results included), $1 / 1k pages for /contents, $12–15 / 1k for the deep tiers, with $20 in free credits for new accounts. This blog's CLAUDE.md puts Exa first among cloud fetch tools, 16 of its 38 skills reference it directly, and only four existing posts mention it in passing — with zero dedicated posts. This is that post.
Firecrawl puts single-page scraping, site discovery, whole-site crawling, and JSON extraction behind one API. Cloud removes browser, proxy, and worker operations; self-hosting gives infrastructure control, but not the complete Cloud feature set.
Free access is not one model: recurring allowances, balance top-ups, rate-limited access, one-time credits, and self-hosting have different steady-state costs.
Linkup separates search depth from response shape: start most agent queries with standard + searchResults, move to deep only for multi-step browsing, and treat the monthly $20 as a balance refill rather than a new $20 grant.
LlamaIndex (51,775 GitHub stars, MIT, verified 2026-08-21) has moved its center of gravity from indexing to Workflows: the standalone llama-index-workflows package pulls 2.81M weekly PyPI downloads, more than the 1.97M of the llama-index umbrella package itself. This post covers the core abstractions, the trade-off against hand-rolling a pipeline, and a hands-on test of its defaults on Traditional Chinese text — at the same chunk_size=1024, English fits 4,645 characters and Traditional Chinese only 1,332. Plus one fact you need before choosing: the TypeScript port is archived and unmaintained.
Meilisearch turns application data into fast, typo-tolerant full-text search; the hard parts are index settings, asynchronous tasks, Chinese tokenization, access filters, and tested recovery.
Microsoft merged Semantic Kernel and its own AutoGen into Microsoft Agent Framework, which hit 1.0 GA on 2026-04-02 for .NET and Python (Go is still public preview). The absorbed autogen-agentchat has not shipped since 2025-09-30. But AG2, the fork on the original authors' side, never merged — it shipped 1.0.2 six days ago, and `pip install autogen` gets you AG2, not Microsoft. This post covers MAF's abstractions, the migration clock, and how to read the tangle of names.
MIT 6.S191's 2026 edition publishes nine lecture videos, slides, three software labs, and solutions, making it an A3 self-study course. The supplied path still depends on Google/Colab, Comet, and OpenRouter for Lab 3, while unaffiliated learners do not receive MIT credit, project feedback, or API credits.
Modal is a per-second-billed serverless GPU platform that also treats agent sandboxes as a first-class primitive (company-reported: over 1 billion sandboxes launched, more than a third of revenue). The selection question isn't how convenient it is — it's your GPU utilization. Verified 2026-08-21: Modal's A100 80GB works out to $2.50/hr against RunPod's $1.59/hr for the same card, so above 64% utilization renting your own is cheaper. But on the same day, H100 SXM is $3.95/hr on Modal against $3.99 on Lambda — on that card the premium is gone.
Qdrant is not just a place to store embeddings: define the vector schema, index frequently filtered payload fields, then add dense+sparse queries, tenant boundaries, snapshots, and monitoring to build an operable retrieval service.
Scrapling puts HTTP, Playwright browsers, CSS/XPath extraction, and a Spider API behind one Python interface. Adaptive selectors save element properties and relocate a target by similarity after a layout change, but the output still needs validation.
SearXNG is a metasearch engine, not a crawler, and it does not own a web-wide index. Based on the official 2026.8.20 documentation, this guide covers Compose installation, settings.yml, engine selection, the JSON API, and empty-result diagnosis.
Three components, one job each: SearXNG finds, Crawl4AI reads, and a thin layer of your own code glues them together. Three defaults will stop you cold — `formats` only emits HTML, `secret_key` ships as the literal string `ultrasecretkey`, and turning on the limiter blocks your own code. Also, the official install path changed in March 2026, so most tutorials online point at a repository that is now archived.
Tavily and Exa are cloud-only APIs and can't be self-hosted. What you can assemble instead is SearXNG (269 upstream engines, 82 on by default) plus Crawl4AI (78.8k stars, Apache-2.0), and the ready-made Tavily-compatible wrappers are all still double-digit-star solo projects you should not depend on. But SearXNG has no index of its own, and running it from a datacenter IP gets you empty results — those two facts decide whether self-hosting is worth it.
CS124 is the first course in Stanford's NLP track: ten weeks from tokenization, n-grams, text classification, information retrieval and embeddings to LLMs and Transformers. The textbook is the free Speech and Language Processing, and the nine assignment repos plus the lab problems and solutions are public; the pre-recorded videos, quizzes and autograding need a Stanford account.
CS221 is Stanford's course on AI principles and techniques. It lays AI out in four layers — reflex, states, variables and logic — with deep learning as only the lowest one. The executable Python lectures and all eight assignments, with code skeletons and a local grader, are public; lecture recordings, hidden test cases and assignment solutions are not.
CS224N is Stanford's course on natural language processing with deep learning: it goes from word vectors and backpropagation to Transformers, every later lecture builds on Transformers, and the four assignments include writing a decoder-only Transformer yourself. The current slides and assignments are public, and Assignment 3 ships unit tests that run on a laptop; the complete public recordings come from an earlier offering and no longer match the current syllabus.
CS224U is Stanford's natural language understanding course, the follow-on to CS224N: it covers domain adaptation for sentiment analysis, retrieval-augmented in-context learning, advanced behavioral evaluation and analysis methods, with a bake-off attached to each of the three assignments. The material is a public GitHub repo, and the slides and the full recordings of the online version are public too; the data loading in the first assignment needs a fix before it runs in a fresh environment.
CS224V is Stanford's Agentic AI course: it teaches how to constrain LLM agents with formal semantics, knowledge graphs and formal methods so they fabricate less, with two assignments and then a project that carries most of the grade. The fourteen lecture decks, the reading list, the assignment handouts and the open-source systems the course uses (STORM, WikiChat, SUQL, Genie Worksheets) are public; there are no public recordings, the posted slides are deliberately incomplete, and the credentials the assignments need go only to enrolled students.