Vamshavalis — king-lists and dynastic chronicles: the Gopalarajavamshavali (14th c., oldest), the chronicles translated by Daniel Wright (History of Nepal, 1877), and genealogies of ruling houses (Malla, Sen, Shah) — indispensable for chronology, but to be read critically: they compress, mythologise and legitimise.
Critical use of sources (the historian's — and the lawyer's — rule): establish authenticity (is it genuine?); date it; ask its purpose and bias (whose voice is it?); corroborate (one source is testimony, two converging are evidence).