diff --git a/CLAUDE.md b/CLAUDE.md
index d56da6e..bc3e2b6 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -7,7 +7,7 @@ This file provides guidance to Claude Code (claude.ai/code) when working with co
 - Frameworks: none detected from the supported starter markers.
 
 ## Verification
-- Run Rust verification from `rust/`: `cargo fmt`, `cargo clippy --workspace --all-targets -- -D warnings`, `cargo test --workspace`
+- Run Rust verification from repo root: `scripts/fmt.sh --check`; for formatting use `scripts/fmt.sh`. Run Rust clippy/tests from `rust/`: `cargo clippy --workspace --all-targets -- -D warnings`, `cargo test --workspace`
 - `src/` and `tests/` are both present; update both surfaces together when behavior changes.
 
 ## Repository shape
diff --git a/scripts/fmt.sh b/scripts/fmt.sh
new file mode 100755
index 0000000..e46e46e
--- /dev/null
+++ b/scripts/fmt.sh
@@ -0,0 +1,5 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+cd "$(dirname "$0")/../rust"
+exec cargo fmt "$@"