In the last 4 hours, SmokeDetector has reported 60+ errors when making normal requests to the SE API. These are the same requests which SmokeDetector has been making many thousands of every day since 2016.
The errors we're currently seeing are typically "Error: no method found with this name" for requests to URLs such as https://api.stackexchange.com/2.2/questions/{postIDs}.
In the last few hours, I've also seen a few similar errors reported in my browser console from userscripts which have been trying to do their normal accesses to the SE API. I don't typically watch the browser console, but I was looking at it for other reasons and happened to see a few of these. There are probably quite a few more that I haven't seen.
Since 2016, SmokeDetector has, on average, reported such SE API errors 47.5 times/year. With 60 errors in 4 hours, that makes an annualized error rate of 131,490/year, which is 2,768 times higher than "normal".
Back in May, in "SE API quota_remaining property is periodically missing from the response", I reported that the error rate for the SE API was noticeably increasing. As of late September, it was at 11.78 times higher than the "normal" which we'd seen over the last 6 years. It's now dramatically higher.
Something is wrong. This isn't status-bydesign.
/questionsalso fail