Titanfall on PC won't offer any sort of modding tools when the game launches on March 11, 2014. Co-founder Vince Zampella confirmed this on Twitter when a fan asked him, but he did add that the studio "will have to evaluate after launch" for the need of mods.
I've never been big into the modding scene, so this doesn't really bother me. What I do want to know is what they're going to do about the server situation. After SimCity and now Battlefield 4, I'm concerned with how the game will handle especially with its heavy dependance on servers.