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Interactive views Simple Loop AI Agent — a prompt, the model's tool calls and the answer, with the JSON of every request, the context window, and a skill RAG AI Agent — the agent searches the notes on every prompt and puts what it finds in front of it, before the model sees it MCP AI Agent — tools on other companies' …

Five pages covering the pieces you actually touch in the LangChain 1.x stack: one per package for building an agent, and two for retrieval. Every entry says what the class or function defines or does, links to the official API page (opens in a new tab), and ends with a runnable example whose printed output was verified …

On this page: What langchain is in 1.x Index Pinned versions: langchain==1.4.0 (released 2026-09-03), which resolves langchain-core==1.6.3 (1.6.2 when these examples ran), langgraph==1.2.11 and (for the one live example) langchain-anthropic==1.7.1. Everything below was derived by inspecting these exact installed …

On this page: langchain Packages What langchain-core is Index langchain Packages Version of langchain-core referenced here: langchain-core==1.6.3 (released 2026-09-11). The examples were derived by inspecting the installed package and executed against it on Python 3.13 This page is a part of a five-page set (see how …

On this page: What langgraph is Index Pinned version: langgraph==1.2.11 (released 2026-08-11; it pulls in langgraph-checkpoint 4.2.0, langgraph-prebuilt 1.1.0 and langgraph-sdk 0.4.4; the SqliteSaver example also needs langgraph-checkpoint-sqlite==3.1.1). Everything below was derived by inspecting this exact installed …

You already know how to clone, branch and merge. This lab adds one more tool: git worktree, which lets a single repository have several working directories checked out at the same time. Why it matters: one working directory can hold only one branch at a time. That is fine for one person doing one task. It breaks the …

Watch a packet travel from host to server. How to read it Each tower is a device, and each square is a layer of the TCP/IP stack (4 layers, not OSI's 7): Physical, Link, Internet, and Transport — applications live above the stack (the dashed boxes) and use it through sockets: 4-square tower — a host: the full stack up …

Web Security Part 1: Basic HTTP Authentication — a client and a server exchanging HTTP messages step by step: the 401 challenge, the password in every request, and what a session cookie adds Part 2: Cookies and Sessions — a form login, the cookie that carries the session from then on, and the record behind it, in the …

For a random IPv4 address + mask (e.g. 178.178.178.178/24), answer three things: Class — is the address Class A, B, or C? Scope — is the mask the class's default, a subnet (longer than default), or a supernet (shorter than default — aggregating multiple classful networks, e.g. 193.15.4.7/16 is one address in a block …

This configuration starts by creating a pair of keys and handling them on linux. This is good also for tasks like connecting to a remote machine in the cloud. At the end, we also go through using this for github (so adding the public key to a github account). Add SSH key To work with github or connecting to a remote …