[Note: The Reputation check's requirements are complex. First, there are factors which seem to be purely pass/fail; missing even one of them flunks the Reputation check: Shepard must have at least four bars of Reputation. Tali and Legion must both be present, which requires an imported save from Mass Effect 2. If no save was imported, Tali will have been exiled and will not be able to support Shepard with an Admiral's authority, while Legion will not appear at all. The mission Rannoch: Geth Fighter Squadrons must be completed.

Additionally, there are other factors which build up Shepard's trustworthiness to both parties; if Shepard has not done enough of them, the Commander will not have the groundswell of goodwill needed to moderate a cease-fire. According to the official Prima Games guide, each factor has a certain "point" value, and at least 5 "points" are necessary for the cease-fire to occur. These factors are: (+2 points) Destroying the heretic geth in Legion: A House Divided. In shipboard conversation, you can ask Legion about the repercussions of your decision, and it will mention that the absence of the Heretics made the consensus to join the "Old Machines" more difficult to achieve. Geth forces are also considerably weakened without the aid of the Heretics, giving the Migrant Fleet an edge in the battle and reducing the quarians' overall casualties. (+2 points) Preventing Tali's exile in Tali: Treason without presenting evidence of Admiral Rael'Zorah's experiments on the geth. While it's possible to present the evidence and still be able to broker peace, it adds its own problem in that it makes Tali far less likely to survive the attack on the Collector Base. (+1 point) Brokering a peace in the Tali/Legion loyalty argument. If the player did not have sufficient Paragon/Renegade points at that time, loyalty of either Tali or Legion would have been lost. In that case -- even if loyalty had been regained later -- this "point" will not count towards the five needed to pass the Reputation check (and broker the ceasefire). (+1 point) Completing Rannoch: Admiral Koris. (+1 point) Saving Admiral Koris during Rannoch: Admiral Koris.](/spoiler "ME3")