AI Chatbot
A multi-turn conversational AI with streaming, a persistent system prompt, configurable context windows, and real-time token/cost tracking — you build the conversation loop yourself, not a wrapper around a chat UI.
A project-based path through AI systems engineering. Every concept is introduced because it solves a real engineering problem — you read, build, break, evaluate, and reflect.
Two formats, one source of truth.
.md files (e.g. source/lesson.agent.md) are the canonical, dense versions written for
LLM / agent consumption. .html files (e.g. rendered/lesson.html) are the
progressive, visual versions for human learners. When they differ, the Markdown agent version wins.
Browse the rendered Source Map for every source note.
A multi-turn conversational AI with streaming, a persistent system prompt, configurable context windows, and real-time token/cost tracking — you build the conversation loop yourself, not a wrapper around a chat UI.
An interactive tool that visualizes how text gets tokenized before any LLM sees it, and how embeddings represent meaning as vectors you can compare by similarity.
A semantic search engine over a corpus: embed documents, store them in a vector database, and retrieve the most relevant results by meaning — with no keyword matching.
A RAG system that ingests PDFs, chunks and indexes them, retrieves relevant sections, and generates grounded answers with citations — plus a faithfulness check that detects hallucination.
A persistent memory system that gives an AI assistant memory across conversations — scoring memories on relevance, recency (exponential decay), and importance, across episodic (what happened), semantic (what is true), and procedural (how to do things) kinds.
A context-aware coding copilot that reads your codebase through tools — file read, directory listing, code search — and answers grounded in the real files, not a guess. The learning target is tool use and the agentic loop (ReAct): the model requests a tool, you execute it, feed the result back, and repeat until it answers.
A reusable evaluation harness for measuring AI system quality: LLM-as-a-judge scoring, a pass-rate decision, and regression testing — re-score a frozen dataset after a prompt/model change and catch what got worse. The learning target is the judge (prompt + robust parse) and turning scores into decisions, with its biases (position, verbosity, self-enhancement) reproduced as failure analysis.
An autonomous, multi-step agent built by making Project 06's tool loop reliable: loop/stuck detection, a steps-and-tokens budget, tool-error recovery, and run evaluation (completion, efficiency, cost) — plus the judgment of when not to use an agent at all. The tool layer is provided; the learning target is the reliability layer that keeps an autonomous loop from going wrong.
The capstone: a personal AI operating system that orchestrates memory, retrieval, the agent, and evaluation behind one routing front door for personal knowledge management. The direct prototype for StarcallOS patterns.
Optional, off-spine labs that go deeper on a focused topic. Not part of the numbered 1–9 sequence and they gate nothing — take them after the prerequisites listed on each card.
Stop hand-wiring tools into one app loop. Wrap Project 05's memory system as a Model Context Protocol server — tools, resources, and a prompt — then consume that one server from two different hosts. The learning target is the provider/consumer split (M×N → M+N): turning a subsystem into a reusable protocol surface, with a real trust boundary. The backend and transport wiring are provided.