I'm a writer rather than a programmer, and I'm interested in creating a proofreading tool tailored to the style rules and formats I use at work. General grammar checkers catch spelling and common grammar mistakes, but they usually don't enforce specialized conventions such as AP Style or an organization's own formatting requirements. How difficult would it be to make something like this, and are there affordable ways to customize an existing tool instead of building an entire grammar checker from the ground up?
3 Answers
This is definitely feasible, especially for personal use. There are already style checkers that support AP conventions, but you may get more value from creating a custom ruleset for the specific guidelines you use. That way you can add or change rules as your work evolves without recreating the whole system.
Building a full grammar checker from scratch would be a very large project. The difficult part isn't just matching words or punctuation—it's handling language context and deciding whether a sentence is actually wrong. It would be much more practical to customize an existing proofreading tool and add your own style rules.
LanguageTool could be a good starting point. It lets you define custom XML rules for things such as preferred wording, punctuation, capitalization, and formatting patterns. You'd still need to learn a little about how its rules work, but that's far less demanding than programming a complete natural-language-processing system, and it can be done without spending a lot of money.

Personal use is the main goal. AP Style was just an example—the real idea is being able to adapt the checker to whatever guidelines I need at the time.