Is the Hadith: "There is no Muslim servant who visits his brother for the sake of Allah except that a caller from the heavens calls out to him, 'You are good, and Paradise is good for you,' and Allah says in the dominion of His Throne, 'My servant visited for My sake, and his reward is My responsibility, so Allah is not pleased for him with a reward less than Paradise'" authentic?

The aforementioned hadith (definition) has a weak chain of narration (is ضعيف الإسناد) because it was narrated solely by weak narrators (ضعفاء) such as Ad-Dahhak bin Hamra, Hammad bin Ja'far, Maymun bin 'Ajlan, and Maymun bin Siyah (who makes errors in his individual narrations). However, the virtue of brotherhood for the sake of Allah and visiting one another for His sake is established by authentic hadiths, including the hadith of the seven whom Allah will shade in His shade, and the hadith of the angel whom Allah sends to one who visits his brother for His sake.