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Hallucination

As explained in Coding with AI

An AI-generated output that is fluent or confident but factually incorrect, nonsensical, or unsupported.

A hallucination is fluent or confident AI output that is factually wrong, nonsensical, or unsupported. Coding models can produce code that looks correct while hiding serious problems. section 1.5 section 1.5.2

LLMs predict likely words and code patterns rather than retrieving answers from a truth database. Faulty training data, tricky prompts, or misleading learned patterns can therefore produce confident errors. section 1.5 section 1.5.2

Watch for hallucinations when generated Python code:

  • Uses a familiar but suboptimal pattern, such as a list where a set would be more efficient. section 1.5.2
  • Chooses a popular library unnecessarily or works only for common cases while failing on edge cases. section 1.5.2
  • Repeats outdated Python practices from codebases written before newer language features. section 1.5.2

Review generated Python

A generated solution may look polished while selecting a list instead of a set, ignoring an edge case, or following an outdated Python pattern. Check the implementation against Python best practices and project architecture before using it. section 1.5.2

How Coding with AI covers it

How deep it goes
Explains prediction and training-data causes, then stops short of presenting a detection algorithm or formal model.
Examples
Uses flawed code, inefficient list choices, unnecessary libraries, edge-case failures, and outdated Python patterns as examples.
What you can do after
Diagnose/debug with it by checking generated code against facts, edge cases, Python practices, and project architecture.
How it connects
Connects hallucination with LLMs, statistical prediction, training data, edge cases, and human oversight.

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This explainer was generated by Manning's knowledge graph from the text of Coding with AI. The section links point to the parts of the book it draws on.