Which types of Webmaster Tools errors should I report to Google?

Matt's answer:

Today’s question comes from StevieD in Mississippi, and StevieD asks a slightly controversial question, at least around here, by saying, how active is Google Webmaster Tools monitored by Google? Specifically, when there is a system error such as the recent error in reporting the number of pages indexed. Does Google need users to report the errors or does Google know about the errors happen as fast as us? Well, StevieD, you’ve essentially asked the engineering equivalent of: did you fart? Because if you ask at Google, do you monitor for errors? That’s a little bit kind of impolite. It’s almost like, well of course I monitor for errors. So just to be safe I pinged the Webmaster Tools team and I said, hey we track these errors and keep an eye on them right? And got back just a couple very, very polite but slightly indignant responses. You know along the lines of we have extensive monitoring for our front end, we make our pipe lines run regularly, we monitor this and that, so the short answer is when crazy errors fly out, whether they be system errors or whenever things are not running correctly, we have a wide variety of things to monitor that and try to track that so that we can fix it ourselves. Because we don’t want to rely on users to have to report that to us. Now the one thing you might think about is if there’s data quality issues. So for example, you used to see this many number of back links and suddenly you’re seeing half as many back links or something like that. We would do a pretty good job of monitoring, well the entire pipeline is broken, or people are getting system errors when they’re trying to access this page, but it’s harder to write safeguard checks to sort of say, oh yes. How how good is the quality of the data? So if you see problems like that definitely let us know. The webmaster forum is a great place to do that, but yeah, I pinged a couple people and got back very quick replies that said, yes, of course we monitor all those sorts of errors. And in fact I think within any engineering team at Google you’d usually get back that sort of response. They’d say, well of course we keep our eye out for these sort of errors and try to fix them immediately. It’s a perfectly reasonable, completely normal question to ask, but you might be aware that you know, that’s a little like poking at an engineer and saying, hey are you a good engineer or not? And I think they take it very seriously here. So always if you see problems, feel free to let us know on the webmaster forum, but I think we’re in pretty good shape on that point.

by Matt Cutts - Google's Head of Search Quality Team

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