toxicTom: You seem to have a very different definition of "tool" from the rest of the world.
A tool is some thing that may help you accomplish a task. A knife is a tool for cutting stuff, regardless if the stuff you try to cut with it can be cut, should be cut or you cut it wrong. So if the cutting is a success depends on the skill of the one wielding the tool, the material they're working with and to some extend the quality of the knife. Regardless of the outcome - the knife is a tool.
A search engine is a tool for finding stuff on the internet. If it's the stuff you were looking for (ie. reliable information or cat content) depends on the skill of you using this tool (including your ability to evaluate the quality of the result), the quality of the information available and the quality of the search engine. However the outcome and success of your using it - it's still a tool.
Ah, I see the confusion now. You are right, Google IS a tool to search for information.
But the person I am arguing with claimed that "Google is a tool to test the source within minutes". What I tried to show is that it is not. You can not google "is that source reliable". Can you? You have to examine each results carefully and 1. You can never be sure what you read either since there is no certainty that its validity is higher than the link you are examining, 2 . It certainly won't be within minutes.
From your same example, we can view GOOGLE as a sets of stores who sell tools. Let's say you want to dig a hole on your wall to hang a picture. You can ask the store owners "How can I dig a hole on my wall?". One can tell you that you should use a
drill, and the other one can tell you "you should use this
army knife, it is good for digging holes". An other one can recommend a
shovel, which is certainly perfect for digging holes.
Which one will you listen? You will listen to your common sense of course. But what if the concept is not clear to you as it is in this example?
Follow up questions; Are the store owners "tools" for finding information? Are they useful to get the job done? Are they reliable and can you trust them?
The answer is, and always will be no. You can NOT trust them. They may be of some help of course, but in the end, the end result will never be sure. That's why the OP did the right thing to come here and ask the question to people who may or may not have the answer. And s/he got it.
Summary, Always ask more stores before buying anything. :)