Sahih Muslim 4630
صحيح مسلم#4630SahihIt has been narrated on the authority of Abu Ishaq, who heard Bars' b. Azib say:When the Messenger of Allah (ﷺ) made peace with the people of Hudaibiya, 'Ali drew up the agreement between them, and so he wrote: Muhammad, the Messenger of Allah. (This is followed by the same wording as we have in the previous tradition except the omission of the words: This is what he has settled)
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 32:112