how to instruct agent to use LSP first, <some tool> second, and only built-in grep/find as third?

[charger89]

Instead of relying on grep/find and others, some users are using fff instead, which instructs users to add following claude.md instruction:

For any file search or grep in the current git-indexed directory, use fff tools.

What would be the correct way to configure our agent to first use Serena's LSP, use fff as a fallback, and only use grep et al. third? Only thing I can come up with is customizing the system prompt (e.g. here), to add fff usage as a secondary tool, and grep & friends as tertiary.

Would that be reasonable, or are there better/more convenient methods?