Here's a couple of common criticisms that will easily identify a commenter as having not read the agreement:
"the TPP (or ISDS) allows companies to sue countries for lost profits" (they don't)
"this is a power grab by pharmaceutical companies" (Pharma was second after Tobacco at being upset with the deal)
"it undermines Net Neutrality" (there are specific points allowing net neutrality regulation, NN was an Obama policy plank FFS)
"TPP worsens environmental or labor conditions" (it actually provides minimum standards that will improve these in developing countries specifically around overfishing, trade of endangered animals, and minimum wage. It's why the deal was endorsed by the WWF)