McLaren announced the signing of Piastri to replace Daniel Ricciardo for 2023 in September following a contract saga involving the Australian's former team, Alpine, that was ultimately settled by F1's Contract Recognition Board.
Alpine initially showed little sign of budging from its existing contract to allow reserve driver Piastri to link up early with McLaren.
But Autosport revealed last Saturday that a deal had been struck for him to feature in the end-of-season test in Abu Dhabi, after it emerged Piastri had recently completed a private test in McLaren's 2021 car at Paul Ricard.
McLaren team principal Andreas Seidl confirmed an agreement had been struck with all parties involved so Piastri could do the test at Paul Ricard, as well as featuring in the single day of running at the Yas Marina Circuit on 22 November.
It will give Piastri a chance to sample McLaren's 2022 car and get a first look at its procedures, as well as allowing the team to understand some of his needs ahead of next year.
"Kilometres nowadays in Formula 1 cars for race drivers are quite limited with the regulations that are in place, especially when it comes to running the current car," said Seidl.
"Therefore it's obviously a very important test for us, to get an initial read from Oscar's side as well on our car and give him an initial feeling, which is then simply the starting point of making sure we get him ready for Bahrain next year.
"We have a good programme in place. I think we have a lot of experience as well in getting young drivers ready for the first race in Formula 1. That's obviously the objective.
"We want to try as hard as we can together with Oscar, that the first race in Bahrain next year actually doesn't feel like it's the first race for him in Formula 1.
"The young driver test is obviously an important starting point, I would say."
Teams will be permitted to run two cars in the Abu Dhabi test. One must be driven by a young driver with fewer than two grand prix starts, while the other will be taken by a 2022 race driver to conduct Pirelli tyre testing.
Further testing opportunities for Piastri ahead of his F1 debut will be limited, with just three days of pre-season running scheduled in Bahrain next February.
McLaren has conducted an extensive private testing programme through this year with drivers including Pato O'Ward, Colton Herta, Alex Palou and Jehan Daruvala, with Piastri being the latest to drive the MCL35M car from 2021.
But Seidl said there was "not too much" to read into Piastri's test at Paul Ricard, given it was a car under old regulations and without any reference.
"It was a good start from Oscar, together with us, and that's pretty much it for the moment," said Seidl.
"The main thing is now, also within the team, to have full focus on these last two race weekends, together with Daniel, who is still committed on both sides to really try to finish our chapter together on a high.
"Then we will switch full attention to Oscar and Lando, and get both ready again for next year's season."
