Lesson 1227 of 1455
What People Mean When They Say 'AI Agent'
'Agent' is the buzzword of 2025-26. Stripped of hype, it means: AI that can take actions, not just generate text.
Builders · AI Foundations · ~5 min read
The big idea
An 'AI agent' is just an LLM connected to tools — search engines, APIs, code interpreters, file systems — that the model can choose to use to accomplish a goal. The model loops: think → decide on a tool → call it → read the result → think again. Real autonomy is still limited, but the basic loop runs every minute on millions of computers now.
Some examples
- Claude Code, Cursor Agent, and Devin are coding agents — they read your codebase, write changes, run tests, and iterate.
- Manus and Genspark are general-purpose web agents — they browse, fill forms, and complete multi-step tasks online.
- OpenAI's Operator can use a real browser on your behalf to book restaurants, order groceries, or fill out forms.
- The simplest agent is a 5-line LangChain script: LLM + 'search the web' tool + 'do math' tool + a loop.
Try it!
On chatgpt.com, ask 'Use the web to research X, then write me a 3-paragraph summary with sources.' That's a 1-step agentic loop already running for you. Now imagine 50 steps. That's where the field is going.
Key terms in this lesson
End-of-lesson quiz
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Lesson help
Questions are best handled with a grown-up here.
For this age range, Tendril keeps freeform AI chat paused until parent/guardian consent and child-safe moderation are fully verified. Use the quiz, notes, and related lessons below, or ask a parent, guardian, teacher, or librarian to work through the question with you.
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