This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Ask what a Purana is for and the usual answer involves cosmology, the ages of the world, the deeds of gods and the genealogies of kings. The Agni Purana answers the same question very differently. Alongside its share of cosmology and divine narrative sit chapters on how to lay out a temple's foundation, how to consecrate the image once the building stands, how a king should govern and go to war, how a physician should diagnose disease, how a poet should scan a verse, and how to judge the quality of a gemstone. No other Mahapurana ranges this far outside religious narrative in its own right.
That breadth is not accidental disorder. Traditional India organized much of its technical and professional learning inside frameworks that a modern reader would call religious, treating architecture, medicine and statecraft as knowledge properly transmitted alongside sacred narrative rather than separated from it. Read that way, the Agni Purana is less a scripture that wandered off topic than a working encyclopedia of the practical arts a well ordered kingdom needed, gathered under a Puranic frame because that was the vessel available for holding organized knowledge and passing it on.
The cost of that ambition shows in the text's own history. A single-purpose scripture stays relatively stable because every generation needs roughly the same thing from it; a working reference on everything from temple ritual to sword fighting invites constant supplementation as new practical knowledge accumulates, which is very likely part of why the Agni Purana grew as long and as unevenly as it did.