Stage 1 · Lesson 3 of 6
Completions, chat and agents
You use these tools in three ways. suggest the next lines as you type, shown as grey you accept with Tab. Chat answers questions about code and can propose edits.
An agent goes further: it reads files, edits several of them and runs commands in a loop until it thinks the task is done. Each level hands over more of the work, so each needs more checking. A two-line completion can be read in a second.
An agent that touched twelve files, installed a package and ran a migration needs a proper review, like a colleague's . Most tools now offer all three, and part of the skill is choosing the lightest one that fits the task.
Common trapreviewing an agent's multi-file change with the same quick glance you give a one-line completion.
A question to check yourself, an AI practice session and 1 cheat sheet entry come when you add the roadmap to your account. Add it
Resources for this stage
Start with· follow one of these
- VideoFreeDeep Dive into Large Language Models like ChatGPT
Andrej Karpathy · Intermediate
A clear, free explanation of how language models are trained and why they hallucinate; watch the first hour
- CourseFreeClaude Code 101
Anthropic · Beginner
Anthropic's free starter course: what an agent is, the agentic loop, context and permissions