Be aware of Yellow Stainer Mushroom. It can be easily mistaken with other Agaricus mushrooms. It causes gastrointestinal disturbances, including stomach crumbs, vomiting, nausea. It is not deadly poisonous mushroom but can destroy few days of your life. Some people are resistant to its toxins, however I would not recommend to eat them. They are easy to recognise as they stain bright chrome yellow when bruised or cut, especially cap and base of the stem. some of them don’t stain straight away, for that microwave test is recommended. Place the mushroom in microwave for 20 seconds, it will spread up yellow staining process. Also it has very unpleasant phenolic odour when cooking. Just not the one for the pot.