pi-reflag

A pi coding agent extension that transparently rewrites grep commands to rg (ripgrep) before they execute — faster searches with zero agent behavior change.

Install

pi install npm:@piotr-oles/pi-reflag

Requires rg on $PATH. Install ripgrep via your package manager if needed:

brew install ripgrep      # macOS
apt install ripgrep       # Debian/Ubuntu

How it works

Intercepts bash tool calls in the tool_call event. When the command starts with grep (including piped commands like grep … | head), it translates the arguments to their rg equivalents and rewrites the command in place before execution. The agent never sees the rewrite — only a user-visible toast notification is shown.

What gets translated:

grep flag	rg equivalent
-r, -R, --recursive	dropped (rg is recursive by default)
-i, --ignore-case	-i
-n, --line-number	-n
-v, --invert-match	-v
-w, --word-regexp	-w
-l, --files-with-matches	-l
-c, --count	-c
-o, --only-matching	-o
-E, --extended-regexp	dropped (rg uses ERE by default)
-G, --basic-regexp	dropped, pattern converted from BRE to ERE
-F, --fixed-strings	-F
-P, --perl-regexp	-P
-A, -B, -C	passed through
--include=<glob>	-g <glob>
--exclude=<glob>	-g !<glob>
--exclude-dir=<dir>	-g !<dir>/
-s	--no-messages
-N (numeric context)	-C N

Subshell constructs ($(…), (…)) are left untouched to avoid misinterpreting nested commands.

Usage

The extension is active by default. Disable it per-session with the --pi-reflag-grep flag:

pi --pi-reflag-grep off

Thanks

• ripgrep by Andrew Gallant — the fast, modern grep replacement this extension routes to
• greprip-rs by kaofelix — the grep → rg argument translation logic is ported from that project (MIT)

Development

pnpm install
pnpm test
pnpm typecheck
pnpm check

To test changes manually:

pi -e packages/pi-reflag/src/index.ts