How sound is the Hadith: "Do you know what a constricted life is? He said: It is the torment of the disbeliever in his grave, and by the One in Whose hand is my soul, ninety-nine dragons will be set upon him. Do you know what a dragon is? Ninety-nine snakes, each snake having nine heads, that will breathe fire into his body, sting him, and scratch him until the Day of Resurrection?"

The Hadith you inquired about is narrated in Musnad Abi Ya'la and Sahih Ibn Hibban with a good chain of transmission, from Abu Hurayrah (may Allah be pleased with him), that the Messenger of Allah (peace and blessings be upon him) said: “And the believer in his grave will be in a garden, and his grave will be widened for him seventy cubits, and it will be lit for him like the moon on a full-moon night.” Then the Prophet (peace and blessings be upon him) recited the words of Allah the Almighty: (But whoever turns away from My remembrance – indeed, he will have a restricted life, and We will gather him on the Day of Resurrection blind) [Taha: 124], and he asked the Companions: “Do you know what the restricted life is?” They said: Allah and His Messenger know best. He said: “The torment of the disbeliever in his grave. By Him in Whose Hand is my soul, ninety-nine dragons will be unleashed upon them,” and he explained the dragon as “ninety-nine snakes, each snake having seven heads, blowing into his body, stinging him, and scratching him until the Day of Resurrection.”