Lesson 1150 of 1570
Why ChatGPT Confidently Suggests Code That Doesn't Run
AI chatbots can't actually run your code — they pattern-match what code usually looks like, which sometimes invents APIs that don't exist.
Lesson map
What this lesson covers
Learning path
The main moves in order
- 1The big idea
- 2hallucination
- 3API invention
- 4verify code
Concept cluster
Terms to connect while reading
Section 1
The big idea
When ChatGPT or Claude writes code, it's predicting tokens, not executing them. It's seen millions of similar snippets and stitches together what looks right. That means imported functions might not exist and library versions might be wrong — confidently.
Some examples
- Claude suggests `array.sortBy()` in JavaScript — but that method doesn't exist in vanilla JS, only in Lodash.
- ChatGPT writes `from openai import ChatCompletion` using an old API style that broke in v1.0.
- Copilot autocompletes a `df.merge_asof_unique()` pandas call that isn't real.
- Cursor invents a Tailwind class like `bg-gradient-rainbow` that doesn't ship with the framework.
Try it!
Ask an AI for a small script using a library you know well. Read carefully — try to catch one made-up function before you run the code.
Key terms in this lesson
End-of-lesson quiz
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