A commentarial work included in the Canon as part of the Khuddakanikāya. It is generally divided into two books: the Cūḷaniddesa and the Mahāniddesa.
The Cūḷaniddesa contains comments on the Khaggavisāṇa Sutta and the sixteen suttas of the Parāyana Vagga of the Suttanipāta, while the Mahā Niddesa deals with the sixteen suttas of the Atthaka Vagga.
It is significant that the Cūḷaniddesa contains no comments on the fifty-six introductory stanzas (vatthugāthā), which preface the Parāyana Vagga as at present found in the Suttanipāta. This lends support to the suggestion that at the time the Cūḷaniddesa was written, the Parāyana Vagga, was a separate anthology, and that the Khaggavisāṇa Sutta did not belong to any particular group. Similarly with the Mahāniddesa and the Aṭṭhaka Vagga.
The comments in the Niddesa seem to have been modelled on exegetical explanations such as are attributed here and there in the Tipiṭaka to Mahā-Kaccāna (e.g., Madhupiṇḍika Sutta (M.i.110 f); also S.iii.9) and to Sāriputta (e.g., Saṅgīti Sutta, D.iii.207 f).
There is a tradition (NidA. p.1), which ascribes the authorship of the Niddesa to Sāriputta. There exists a Commentary on it, called the Saddhammapajjotikā, by Upasena Thera. It was written in Sri Lanka at the request of a monk called Deva Thera.