In order for me to approve your annotation, it must meet the following criteria:
1) Be relevant to the highlighted text
2) Provide a summary of the text or a definition of a word ONLY when the language is too difficult for many readers to interpret on their own
3) Be accurate in its analysis or reasonable in its conjecture
4) Include a citation if it's gleaned from other sources and quotation marks if it's a direct quotation
5) Include a caption explaining its relevance if it's an image or a gif
6) Use formal, academic language
7) Be virtually free of technical errors
8) Avoid spoilers when annotating a novel (This is the only circumstance in which you can use vague language)
Just a heads up: Students' most common errors are images without captions, failure to capitalize proper nouns, and run-ons and fragments--lots of them!