Adams joked about this turn of events, describing herself as "the AJ Hackett of New Zealand politics".
"It is always good to hold some of the firsts in this place, and I'm pretty sure I'm the first MP to have retired, un-retired and then re-retired, all before I ever actually left."
Adams said she had spent some time reflecting back on her time in politics, and thinking about what had really mattered.
She believed she could reflect with pride on what she had done.
She spoke of the big speeches that had meant a lot to her personally, including speaking about her mother's death during the euthanasia debate and her speech during debate on the abortion law reforms.
In the latter, Adams had raised concern about the apparent rising conservatism in her party and the risk the party's views were getting more and more out of kilter with those of broader society.
Another highlight for Adams was delivering the apology in 2017 to men with past convictions for homosexuality, "men unjustly convicted of loving who they love."
She also reflected on work as a minister in 16 different portfolio areas. It included her work as Justice Minister on early intervention under the social investment approach championed by Sir Bill English, and on family violence.
Adams added her voice to others who have raised concerns that the "scorn and vitriol" MPs face would deter good people from entering Parliament.
"These jobs are tough. The life is brutal and the public will never really see the hours, the stress, the impossibility of the perfection that is required and the impact that life in the public eye has on our families."
However, she said the job deserved the devotion that it took.
"I've received death threats and abuse and seen my children have to deal with the relentless negativity and lies that are aimed at us through the media and social media alike. Yet not for a moment do I think it has not been worth it."
She said she left with immense pride and some advice for those who followed her.
"Do the right thing and let the politics take care of itself. Be brave. Stand up on the divisive issues and never lose sight of the difference you are able to make in the time you have."
Her valedictory was also peppered with humour.
One of her first encounters with then prime minister John Key was at the parliamentary gym.
She got on a treadmill and found the previous user had left it on "warp speed," jettisoning her through the air to land at Key's feet.
"He looked down at me and said "are you right Amy? Be careful, the ACC budgets are tight."
Adams also recalled crying in Parliament during a speech after the first major Christchurch earthquake:
"As I tried to get a grip on myself I recall Hone Harawira calling out 'kia kaha, sister' and I thought 'holy cow, if Hone is feeling for a filthy Tory like me then I really must be a mess'."
She also recalled a near-miss when her office staff stopped her sending out a letter for a meeting with the iwi leaders "which autocorrect had unhelpfully changed to ask for a meeting with the Isis leaders."
Adams came into Parliament in 2008 in the safe Canterbury seat of Selwyn and was made a cabinet minister in 2011. Her roles included Environment Minister, Justice Minister, Communications Minister and Social Housing Minister from 2016.
