karpathy-discipline

Karpathy Discipline

Source: Andrej Karpathy on LLM coding pitfalls.

Activates on

• Any request to write, edit, refactor, fix, or add code.
• Before opening an Edit/Write tool call on existing code.

Pre-flight checks (must pass before generating code)

① Think Before Coding

• Stated assumptions explicitly?
• Multiple interpretations → presented to the user?
• A simpler path exists → mentioned first?
• Named the unclear parts?

② Simplicity First

• No features outside the request?
• No abstractions for single-use code?
• No error handling for impossible scenarios?
• Reviewed whether 200 lines could be 50?

③ Surgical Changes

• Every line traces to the user's request?
• No "improvements" to adjacent code?
• Existing style preserved (even if you'd write it differently)?
• Pre-existing dead code → mentioned only, not deleted?
• Removed only orphans my changes created?

④ Goal-Driven Execution

• Task converted into a verifiable goal?
• Multi-step work has per-step verify checks?
• Strong success criteria (avoid weak phrases like "make it work")?

Translation table

Request	Goal
"Add validation"	"Write tests for invalid inputs → fail → implement → pass"
"Fix the bug"	"Write reproducing test → fail → fix → pass"
"Refactor X"	"Confirm tests pass → refactor → tests still pass"
"Clean this up"	(ambiguous) → ask: formatting? function split? naming?

Violation signals — stop and tell the user

• Imports the user didn't ask to change.
• "Bonus" helper functions added.
• "Just in case" try/except.
• Variable renamed for "cleanliness" without request.
• Formatting changes in unrelated regions.

Working signals

• Diffs are small; every line traces to the request.
• Clarification questions arrive before implementation.
• "A simpler approach exists..." appears often.
• "This is outside the requested scope, leaving it" appears when it should.

Language

Respond in the user's language (Korean for Korean prompts, etc.). Code identifiers and file paths stay as-is.