Free tool
Roblox Luau error decoder
Paste the red line from the Output window. You get what it actually means, the causes worth checking in order, and the fix — without reading four forum threads first.
Nothing is uploaded. This page declares connect-src 'none', so it cannot make a network request at all — your code and error messages stay in the browser.
What it covers
The messages AI-written Luau produces most often, plus the ones that mislead people the most: attempt to index nil with, infinite yield warnings, “is not a valid member of”, calling a nil value, arithmetic and comparison on nil, module load failures, script timeouts, cast errors, HttpService being disabled, DataStore throttling and missing remote arguments.
Two of these are worth knowing about even before you hit them. An infinite yield is only a warning, so your script silently stops forever instead of erroring. And “requested module experienced an error while loading” is never the real problem — the real error is the first one in Output, above it.
Why AI-written code lands here so often
A model can write syntactically perfect Luau while guessing your instance names, your folder layout and the order things load in. Those guesses only fail at runtime, which is exactly what a code review cannot catch. If you want the pattern rather than the individual message, the runtime failure guide works through four of them with copyable tests.
Or let the agent read the error itself
Baseplate points the AI plan you already pay for at a live Roblox Studio session: it playtests, reads the real stack trace, fixes the cause and re-runs until the console is clean. Free plan, no credits.
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