In any negotiation, it's always the tricky final details that are the hardest to agree on. That has especially been the case in the long, dismal history of failed Middle East peace deals - where "final status" issues like where borders would be drawn, and the location of a Palestinian capital in East Jerusalem, have tripped up negotiators in the final stretch. In this case, it's the reverse situation.
Yes, there's an agreement for a ceasefire, and the release of hostages and prisoners. But almost everything else appears to have been pushed out to be dealt with later - from the date of a full Israeli withdrawal, to who will govern Gaza afterwards, to an implausible "pathway to Palestinian statehood". The last ceasefire between Israel and Hamas fell apart in March, when a second round of negotiations that were supposed to finalise a peace agreement never got underway. This deal is supposedly far more comprehensive. However, some elements directly contradict Israel's "red-line" positions.
All of which means there is any number of ways this could all fall over - perhaps within days.
*Hamas may not disarm.
*The details of Israel's withdrawal are extremely vague.
*No consensus on Gaza authority. Gaza is to be governed by a temporary committee of Palestinians and international experts to deliver day-to-day public services, overseen by a Board of Peace chaired by Trump - until control can be handed over to a reformed Palestinian Authority.
That's not going to happen, according to Netanyahu - and possibly, also according to Hamas.
https://www.rnz.co.nz/news/world/575749/why-the-gaza-ceasefire-could-collapse-over-coming-days