The truth of the matter is that the vast majority of Anglophone speakers are familiar with the writing conventions that govern English.
Square brackets, i.e. [ ] are not normally used in writing, instead (round) brackets, i.e. ( ) are preferred. Likewise, Anglophone speakers have been taught from an early age that questions end in a question mark (?), that the personal pronoun "I" is always capitalised in English; that the word English itself is always capitalised; that a space follows commas, semicolons and periods; that the first letter of a new sentence is always capitalised. They also learn at school not to put a space between the quotation mark and the word that follows, e.g. “Hello, Bob!” Many of these orthographic conventions also exist in Romance languages, so the need to create an AI programme that will fix these basics seems to me redundant. It's one thing not knowing the language very well and making grammar mistakes, quite another not adding a space after a period, not capitalising the first letter at the beginning of a sentence, not using a spell checker, etc. AI shouldn't have to fix this type of sloppiness. A word about spell checkers, not always do they catch out spelling errors, if a word is spelt (spelled) correctly but carries a completely different meaning, a spell checker won't tell you this.
Leaving to one side whether the following excerpt is well-written, or if the word semicolon should be hyphenated, it is formatted and spelled correctly, so it is easy to read.
Use a semi-colon (;) before and a comma (,) after however when you are using it to write a compound sentence. If ‘however’ is used to begin a sentence, it must be followed by a comma, and what appears after the comma must be a complete sentence.
Use a semicolon [;] before anda coma [,] after howeverwhen you are usingit to right a compound sentense .if ' however ' is used to begin a sentense ,it must be followed by a coma ,and what appears after the coma must be a compleat sentense .