This question is the exact opposite of [How do I indicate sarcasm/irony online?](https://interpersonal.stackexchange.com/q/161/1599). Sometimes some of our words that are meant to be understood literally look like sarcastic. When we are indicating that we are sarcastic, we can use /s or /sarcasm. However, when we are indicating that we are honest, we can't simply omit it. (It may be still interpreted as sarcastic). In TVTropes, we can link our text to Sincerity Mode page. 

But consider the following situation: Toei is an anime studio that's infamous for creating anime with filler. Someone told me that Radiant (an anime) should have been made by them because they know how to make an anime popular.

I replied that "I agree. Especially if your anime were going to be filler-ridden anyway". I actually agree that Toei should have made it because they know how to make an anime with filler bearable or even good, not sarcasm that means Toei is a bad choice because Toei only made anime full of fillers. But my message was interpreted as the latter.

**How can I indicate a lack of sarcasm online, to avoid messages being interpreted as sarcasm when they are not?**