Building & Product

What actually is an AI agent, in plain language?

An AI agent is software that uses an AI model as its brain to pursue a goal: it plans the steps, uses tools (your email, browser, spreadsheets, code, APIs), checks its own work, and keeps going until the job is done. A chatbot answers you; an agent acts for you. Think of it as a tireless junior teammate that can read, click, write and call other software, but still needs clear instructions and supervision.

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18 resources.

🎧 Podcast

Three infra investors argue out the definition honestly, including where the hype ends.

What Is an AI Agent?

a16z (Guido Appenzeller, Matt Bornstein, Yoko Li) May 2025

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More in AI Agents

Why would a founder use agents instead of a chatbot or automation? 18 → What real tasks are founders delegating to agents today? 20 → How do I build my first agent without being technical? 20 → Which platform or framework should I build my agents on? 18 → How much do AI agents cost to run, and how do I keep the bill under control? 18 → How do I test an AI agent and know when it's reliable enough to trust? 18 → What can go wrong when an agent acts on my behalf, and how do I keep it safe? 16 → What is MCP, and why does it matter for my agents? 18 → Should I build one agent or a team of agents working together? 18 → Can coding agents like Claude Code actually build my product? 18 → Is there a real startup opportunity in building vertical AI agents? 19 → How should I price a product built on AI agents? 18 → Why do most AI agent projects fail, and what do the winners do differently? 19 → How do I give my agent the right context and memory so it stops forgetting? 18 →

Also in Starting Up

The same ground, over in Build the product, our Starting Up track.

What actually counts as an MVP, and what's the smallest one I can get away with? 20 → Which no-code tool should I use to build my first product? 20 →
eChai Partner Brands The partnership →