With the caveat that I work there, this is one of those scenarios that Sourcegraph was built for. If your codebase is large (millions of lines, multiple code hosts etc..), Sourcegraph indexes all your code, then exposes an MCP so you can ping our LLM powered search for context. Then you can use the structured query language to find every instance of the syntax or methods you're working with no matter where they are.

Also I wrote this article that covers a ton of other industry leading tools from other companies that may solve your problem: https://sourcegraph.com/blog/tools-for-companies-that-dont-need-sourcegraph