diff --git a/scripts/pr-watch-test.sh b/scripts/pr-watch-test.sh
index 685a034f..5293388e 100755
--- a/scripts/pr-watch-test.sh
+++ b/scripts/pr-watch-test.sh
@@ -20,14 +20,14 @@ run_case() {
   [ "$got" = "$want" ] && ok "$name" || bad "$name" "$got" "$want"
 }
 
-# Like run_case but captures stdout for content checks
+# Like run_case but writes output to a caller-provided file.
+# Caller must NOT use command substitution (subshell loses ok/bad counters).
+# $1 name, $2 expected exit, $3 fixture dir, $4 output file, rest: extra args
 run_case_capture() {
-  local name="$1" want="$2" dir="$3"; shift 3
-  local out="$work/output.txt"
-  PR_WATCH_FIXTURE_DIR="$dir" "$WATCH" 1 --interval 0 --timeout 1 "$@" >"$out" 2>&1
+  local name="$1" want="$2" dir="$3" outfile="$4"; shift 4
+  PR_WATCH_FIXTURE_DIR="$dir" "$WATCH" 1 --interval 0 --timeout 1 "$@" >"$outfile" 2>&1
   local got=$?
   [ "$got" = "$want" ] && ok "$name" || bad "$name" "$got" "$want"
-  cat "$out"
 }
 
 mk() { mkdir -p "$1"; cat > "$1/$2"; }
@@ -84,16 +84,16 @@ mk "$work/green-reviews" last.json <<'EOF'
  {"name":"build","status":"COMPLETED","conclusion":"SUCCESS"}]}
 EOF
 mk_reviews_with_review "$work/green-reviews" "aaaaaaaaaaaa" "aaaaaaaaaaaa"
-out=$(run_case_capture "green with reviews shows review output" 0 "$work/green-reviews")
-if echo "$out" | grep -q "pr-reviews:"; then
+run_case_capture "green with reviews shows review output" 0 "$work/green-reviews" "$work/out1.txt"
+if grep -q "pr-reviews:" "$work/out1.txt"; then
   ok "green with reviews prints pr-reviews output"
 else
   bad "green with reviews prints pr-reviews output" "no pr-reviews output" "pr-reviews: in output"
 fi
 
 # --no-reviews skips the review printout
-out=$(run_case_capture "--no-reviews skips review output" 0 "$work/green-reviews" --no-reviews)
-if echo "$out" | grep -q "pr-reviews:"; then
+run_case_capture "--no-reviews skips review output" 0 "$work/green-reviews" "$work/out2.txt" --no-reviews
+if grep -q "pr-reviews:" "$work/out2.txt"; then
   bad "--no-reviews skips review output" "pr-reviews in output" "no pr-reviews"
 else
   ok "--no-reviews actually skips review output"