> For many engineering jobs, P(AI mistake) is very low and decreasing
This is not my experience. Well, at least not for what I'd consider very low.
For example, I have a standard task of adding support for a well-specified regex scheme as a dependency-free module to the Wren language (which grew out of actually needing it at one point). When done autonomously, errors still occur, some of them very basic. For example, trying Fable 5.2 at medium the other day produced the following:
- memory unsafe behavior on 32-bit architectures (the good old problem of size overflowing on an allocation call).
- O(n^2) behavior for searchAll() and replaceAll() operations.
- Various minor subtle semantic issues, though none of them particularly critical.
This is a well understood problem, and in general, Fable's construction (Thompson NFA by way of a Pike VM) was in principle correct, but it still had these pretty basic problems. (Other frontier models produced their own, e.g. a use-after-free bug or a combinatorial explosion in the regex compiler for some types of regexes.)
(As an aside, so far I don't consider Fable 5.2 an improvement over Opus 5.5 in coding ability, more of a sidegrade; while it is smarter and can do some hard, but also pretty esoteric stuff that Opus fails at or takes much longer with, for regular coding problems it's neither better nor worse, more ... different. And sometimes Fable seems to outsmart itself, producing a seemingly clever solution from its vast knowledge that is actually worse than the standard approach in practice.)
One area where I absolutely do not trust even frontier models yet is parallel and distributed programming. I absolutely value them as a second set of virtual eyes for tricky situations in this area, but I do not trust them to get things right, and even if the solution is correct, it's often inefficient or convoluted.