Foundation~135 minHazelJS
Agent Foundations
Beginner foundations on HazelJS: what agentic AI means, how AgentRuntime differs from chat and workflows, when not to use an agent, and the runtime mental model.
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Course promise
Start here if agentic AI is new to you. This track teaches vocabulary and judgment on HazelJS before you write a full production loop.
You will learn what an agent is (and is not), how chatbots and workflows differ, when to stay with a simple prompt or flow, and how AgentRuntime owns a single turn.
Who this is for
- Engineers who know TypeScript basics but are new to agents
- Teams aligning on HazelJS Agent OS language
- Anyone about to start Agentic Development
How to take the course
- Read lessons in order — each checkpoint unlocks the next.
- Keep a sticky note: goal / tools / done check / non-goals for one real feature.
- Prefer understanding over installing every package on day one.
- When finished, continue to the builder track (Ops Desk).
Lesson map
| # | Lesson | You leave with |
|---|---|---|
| 01 | Agentic AI in plain language | Shared vocabulary + sticky-note one-pager |
| 02 | What is an agent? | HazelJS @Agent / @Tool / execute definition |
| 03 | Agent vs workflow vs chatbot | Decision checklist + worked examples |
| 04 | When not to use an agent | Left-to-right rule + premature smells |
| 05 | AgentRuntime mental model | Phase-by-phase execute walkthrough |
Docs: Agent package, Agent OS.
Learning outcomes
- Explain agentic AI and HazelJS agents in plain language
- Choose among @hazeljs/ai, @hazeljs/flow, and AgentRuntime with a checklist
- Walk one AgentRuntime.execute turn and know when not to use an agent
Lessons
- 01Agentic AI in Plain LanguageWhat “agentic” means for beginners: goals, tools, loops, and why production agents need more than a chat box—mapped to HazelJS.
- 02What Is an Agent?Define a production agent through HazelJS AgentRuntime: goal loop, tools, observation, and budgets—explained slowly for beginners.
- 03Agent vs Workflow vs ChatbotChoose among HazelJS chatbots (@hazeljs/ai), deterministic flows (@hazeljs/flow), and AgentRuntime tool loops—with beginner examples and a decision checklist.
- 04When Not to Use an AgentDefault left on the HazelJS spectrum: when a prompt or workflow is enough, premature AgentRuntime smells, and signals that truly justify an open tool loop.
- 05AgentRuntime Mental ModelHow AgentRuntime owns context assembly, tool validation, budgets, checkpoints, and stop reasons—step by step for beginners inside a HazelJS app.
Capstone: One-pager for a real feature: goal, done check, chosen HazelJS shape (ai / flow / agent / hybrid), and why the left option fails.