Update README.md

Added a limitation for the sensitivity to certain characters.

README.md

@@ -29,6 +29,8 @@ Intended to be used to determine if tweets are useful instructions.
 
 The model will be biased towards english data, and maybe be biased towards certain ways of phrasing "instructions". Instructions in this case may also be questions.
 
+Current version of the model is very basic and can get confused by simple things. For example, simply adding a ? character will bias it heavily towards an instruction, even if using the same sentence so it is highly sensitive to certain characters and ways of phrasing things. This can hopefully be fixed by better training data or model tuning.
+
 ## Training and evaluation data
 
 Model was fine-tuned on a relatively small number of tweets and instructions.