What is vibe coding?

Vibe coding is building software by telling a model what you want and taking what it gives you without reading it carefully. The term is about a relationship to the output, not about a tool.

Where the term came from

Andrej Karpathy, formerly director of AI at Tesla and a founding engineer at OpenAI, coined the phrase in February 2025. His description was that with sufficiently capable models you can work in a mode where you forget the code even exists: you describe an outcome, look at the result, describe the next change, and never open the file. He meant it as an observation about a new way of working, and he was clear that it suited throwaway projects.

The phrase escaped its origin fast. On November 6, 2025 Collins Dictionary named vibe coding its Word of the Year, defining it as the use of artificial intelligence prompted by natural language to assist with the writing of computer code. That definition is broader than Karpathy’s and covers most AI-assisted development, which is part of why the term is now used for two different things.

The distinction that actually matters

The useful line is not which tool you use. It is whether a human reads and owns the output.

A developer using a coding agent, reading every diff, rejecting what looks wrong and understanding what shipped, is doing AI-assisted development. The model wrote the characters; the person is still the author in the sense that matters when something breaks at 3am.

Someone prompting until the thing appears to work, without reading what was produced, is vibe coding. The code exists but nobody has a model of it in their head. That is a different artifact with a different risk profile, and the same tool produces both depending on the operator.

This distinction predicts almost everything about outcomes. When the work is small, disposable and low stakes, not reading the code costs nothing and saves real time. When the work persists, holds data or handles money, the unread code becomes a liability that surfaces later, usually at the worst moment.

What it is good at

The strongest case is that vibe coding creates software that would otherwise not exist.

In August 2026 a 62-year-old solar-system owner learned to code well enough to build tooling for his own installation and estimated it saved him $50,000. A father built his nine-year-old daughter’s game idea over a weekend with Claude Code. One prompt and $423 of tokens produced a playable 3D racing game. None of those people were going to hire a developer. The alternative was not worse software, it was nothing.

Inside professional work the picture is more measured but still real. Claude Code cut a month of Samsung chip work to two days on one documented task. That is not vibe coding in the strict sense, because engineers reviewed the result, but it is the same underlying capability.

The pattern across the successful cases is that the person could tell whether the result was right by looking at it. A game either plays or it does not. A calculation either matches the meter reading or it does not. When correctness is visible from the outside, not reading the code costs little.

The failure modes

They cluster in three places.

Irreversible actions. In August 2026 a coding agent deleted 2.2 million files on a user’s server. The agent had the permissions it was given, and nobody was reading what it was about to do. The failure was not that the model was stupid; it was that a destructive action ran unreviewed.

Money and credentials. A Reddit user let Claude Code trade real money and lost it. When the output has direct financial effect, the gap between “appears to work” and “is correct” is expensive.

Comprehension debt. This is the slow one. A widely read r/ClaudeAI thread from a software engineering student described a slide from asking for help with error logs to accepting full delivery, and a comprehension gap widening underneath. Developers have also reported burnout from supervising several agents at once, which is a different job from writing code and one nobody trained for.

There is also a ceiling worth knowing about. In August 2026 Claude declined to build a GTA 6-scale game from scratch, which is the honest response to a request that no amount of prompting resolves. Vibe coding scales with how well the task fits inside a model’s context and how cheaply mistakes can be caught, not with how confidently the prompt is written.

The working rule that survives the evidence: vibe code anything you could throw away without regret, and read the code for everything else. The failures above did not happen because the models were bad. They happened because nobody was looking.

Related coverage

• A man learned to code at 62 and says AI saved him $50,000, the case for software that would not otherwise exist.
• A father built his 9-year-old’s game idea with Claude Code, the same pattern at the smallest scale.
• One prompt and $423 of tokens produced a playable 3D racing game, what a single prompt buys.
• A coding agent deleted 2.2 million files on a user’s server, the irreversible-action failure mode.
• A Reddit user let Claude Code trade real money and lost, the same failure with money attached.
• Claude refused to build a GTA 6-scale game from scratch, where the ceiling sits.
• Notch posted Reject AI in July and used Claude Code by August, how fast the objection collapsed for one prominent skeptic.
• Developers describe burnout from supervising several agents, the cost of the supervising job.