Early and classical Sunni sources preserve a report that the manager of Anas ibn Malik's land complained that it had become dry and needed water. Anas went out, prayed, and supplicated; a cloud then gathered and rain fell over the land until his cistern was filled. When the extent of the rain was checked, the reports say it had not gone beyond his land except slightly, or had not gone beyond it at all. Ibn Sa'd preserves an early route, and al-Dhahabi records a second similar route and explicitly calls the event a clear karamah established through two chains.
According to the fuller reports, Anas went out, prayed, and then supplicated to Allah. After his prayer, a cloud formed or gathered over the land and rain began to fall. The rain continued until his cistern or reservoir was filled. In the fuller al-Bayhaqi form, the event is specifically placed in the summer, adding to the unusual character of the scene.
The report then gives a further detail that became central to its reception as a karamah. Someone was sent to inspect how far the rain had spread. The transmitted forms differ slightly: one says that the rain had not gone beyond Anas's land except a little, while another says that it had not gone beyond his land. These should remain as route-level wording differences rather than be forced into one exact statement.
Ibn Sa'd preserves an early route through Ja'far ibn Sulayman from Thabit al-Bunani. Al-Bayhaqi gives a fuller form through the same general route family, preserving the prayer, the cloud, the rainfall, and the filling of the cistern. Al-Dhahabi also records a second similar route through al-Ansari from his father from Thumama. He then gives an unusually clear assessment, describing the event as a manifest karamah established through two isnads.
This two-route support is important. It means the story is not merely a late repetition of one isolated chain, and the explicit classical grading strengthens its evidentiary standing. At the same time, the exact boundary of the rain should still be reported with the small variation preserved by the sources.
The strongest conclusion is that early and classical Sunni sources strongly preserve a report in which Anas ibn Malik prayed for relief during drought on his land, rain then fell, his water storage filled, and the rainfall was reported to be limited almost entirely or entirely to his property. The event is best presented as a high-confidence Companion karamah and answered prayer, not as a Prophetic hadith.
Conclusion
Early sources and al-Dhahabi's explicit two-chain assessment strongly support the report that Anas ibn Malik prayed for rain and that relief followed over his land in an extraordinary, tightly limited way. The event supports high-confidence inclusion as a Companion karamah centered on accepted prayer.