My conclusion from tipitaka and commentaries:
All tipitaka canons and commentaries, except kathāvatthu the forth of abhidhamma, began before 1st saṅgāyanā, but catagorize at 1st saṅgāyanā (see: DN.Commentary.)
But some tipitaka canons had done at 1st saṅgāyanā, some at 2nd, some at 3rd, and just vinaya-history in parivāra had done after 3rd saṅgāyanā (because vinaya have serious rule about the qualification of vinaya-successor, so list of vinaya-memorized successor's names were required, in parivāra, that began in upāli-thera school).
What canons were done at 1st?
Because of unanimous decision of 500 saṅgha at 1st saṇgayanā, that saṅgha must not add/cut/change any buddha's words off teaching. So this canons must done in 1st saṇgayanā:
- Buddha's literal canons, that was learn & memorized by ānanda, upāli:
- 7 vinaya-pitaka (except sattasatikakhandhaka in cullavagga), parivāra-content (except vinaya-history), 4 nikāya, buddha's literal canons in kuddaka-nikaya.
- Sāriputta's literal canons, that was learn & author by sāriputta-mahāsāvaka and memorized by his students, who were in 1st saṇgayanā instead of sāriputta, who died before 1st saṇgāyanā. Buddha chose to support sāriputta as the best teacher (etadagga) like himself. So no one can change his speech, too. So his canons should had done in 1st saṇgayanā, too:
- Sāriputta's literal sutta in 4 nikāya, sutanipāta, sāriputta-theragāthā, niddesa, paṭisambhidāmagga, sāriputta-apadāna, cariyāpitaka, 6 abhidhamma-pitaka, Mahāaṭṭhakathā (The great commentary).
- In my opinion I think buddha-apadāna and many jātaka are memorized by sāriputta, too. Because of buddhavaṃsa's and cariyāpitaka's characters. And in nidāna of DN.Commentary. also have an conversation between ānanda (dīghabhāṇaka) and sāriputta's students (macchimabhāṇaka) at first saṇgāyana about the categorization of KN. & buddhavaṃsa & cariyapitaka that should include in suttanta or in abhidhamma.
- The other sāvaka's & sāvikā's speech, that were memorized by some saṇgha in 1st saṇgāyanā:
- Sāvaka's & sāvikā's speech that were memorized by ānanda: Itivuttaka, The remaining speech in 4 nikāya.
- Sāvaka's & sāvikā's speech that were told by the owners: Some thera/therīgatha, Some thera/theri-apadāna.
- Sāvaka's & sāvikā's speech that were told by their students: Sāriputta-theragātha/therāpadāna, Moggallāna-theragātha/therāpadāna, etc.
What canons were done at 2nd?
- Some thera/therīgatha, Some thera/theri-apadāna (some thera died after 1st saṇgāyanā such as ānanda, kassapa, anuruddha, upāli, etc.)
- Sattasatikakhandhaka in cullavagga and just sattasatikakhandhaka's commentary. (In my opinion arahanta, in 3rd saṇgāyanā, did not author 3rd saṇgayana history anymore because they realized that it will be over responsibility of future-generations-vinaya-memorizers).
What canons were done at 3rd?
- Kathāvatthu and just kathāvatthu's commentary.
- Commentary about 3rd saṇgāyanā history.
What canons were done after 3rd?
- Vinaya-history in parivāra.
- None-Pali commentaries' translation and extension (andhaka-aṭṭhakathā, kauanadī-aṭṭhakathā, pañcarī-aṭṭhakathā).
- Visuddhimagga and Abhinava-aṭṭhakathā (the combination of commentaries. It is just old commentaries in new package. Buddhaghosa wrote that he never add/edit anything. He just remix fussy/duplicate texts and translate siṇhala commentaries to pali language).
- Abhidhammatthasaṇgaha, abhidhammāvatara, and many conclusion-commentaries.
- Beginner's Buddhist Course Syllabus By Ancient Pali Canon (Ganthadhura And Vipassanādhura)
- Layers of pali literality already being in buddha-living-period. https://buddhism.stackexchange.com/a/21166/10100