As always against Agrest I have seen myself end up in a bad position after the opening. White dominates the open file, black's rook can't move and my seventh rank is weak. White's play is probably to walk with the king to b2 and then open up the king side in one way or another.
26...h5! gains space
27.Td2 Kh7 28.Kf2 Lf5! the exchange will lead to pressure on the g-file and sufficient counterplay
29.e4 Le6 30.Ke2 g5! against Agrest you have to achieve the pawn levers as soon as possible, otherwise you will find yourself in a positional lost position without counterplay. Here I open up in front of my king but it's important that I do this before white's king is away.
31.Kd1 gxh4 32.gxh4 Tg8 33.Kc1 Tg3 34.Kb2 Txf3 35.Td8 I have won a pawn but now I must defend in order to stop Tb8xb7.
35...Tg3 36.Tb8 Tg7 37.Dxa5 Dd6 [37...Tg8= A rook exchange should have been good, then I always have perpetual when white starts advancing his majority.]
38.Dd8 Dxd8?? This is completely stupid and leading to a strategic loss. Here I must understand that a queen exchange is the last thing I want. There was many ways to avoid this and play for perpetual. [38...Ld7 39.Txb7 Dd4+ Draw.; 38...Dc5 39.Dxf6 Dd4+ Draw.; 38...Td7 39.Df8 Dd4+ Draw.]
39.Txd8 White wins with Td6, a5, Kc3, b4 etc. Black will ever achieve ...f5 and therefore he can just wait until the white majority decides. 1-0