I have been asked about the UE Assistance Information (UAI) RRC message a few times before.
Generally I have always pointed people back to the LTE/5G specifications but here is a concise video that the telecoms technology training company Mpirical have shared recently:
Watch on YouTube: 
https://www.youtube.com/watch?v=3n1tD_Cow1Y
Read more details: 
| Topic | Replies | Views | Activity | |
|---|---|---|---|---|
| Check for supported band combination in UE capability Information RRC message | 3 | 4468 | February 9, 2021 | |
| Summarizing 5G RRC Inactive state and comparing with other 5G RRC states | 1 | 3413 | October 23, 2022 | |
| Parameter in gNB to control type1-Singlepanel-ri-restriction IE | 37 | 3146 | June 4, 2021 | |
| Visualization of 5G/NR CSI RS | 0 | 1134 | December 7, 2023 | |
| Spcell and mac-logicalchannel on RRC setup message of 5G NR SA purpose | 12 | 819 | June 30, 2021 | |
| Condition to set 5G-TMSI | 1 | 1859 | December 9, 2020 | |
| Check if UE support SRS 2T4R by measuments | 6 | 741 | July 12, 2021 | |
| 5G NR SA UE attach log (till RRC messages) | 4 | 2212 | November 22, 2021 | |
| 5G NR DCIs - Downlink Control Information | 1 | 1548 | September 22, 2024 | |
| UAC(Unified Access Control)- with 5G USIM | 2 | 2371 | December 15, 2021 |
