4 files changed, 126 insertions, 1 deletions
diff --git a/scripts/install-ai.sh b/scripts/install-ai.sh
index 0c90f64..8c04e22 100755
--- a/scripts/install-ai.sh
+++ b/scripts/install-ai.sh
@@ -179,6 +179,24 @@ case "$track_mode" in
     ;;
 esac
 
+# Ignore temp/ in BOTH track and gitignore modes (not the "not-a-git-repo"
+# case). temp/ is the home for ephemeral, disposable, regenerable artifacts —
+# throwaway regardless of whether the project tracks its .ai/ tooling, so it
+# rides neither the track .gitkeep step nor the gitignore-only tooling block.
+# working/ is deliberately NOT ignored: it's the tracked home of in-progress
+# work, version-controlled from creation (see working-files.md). Idempotent:
+# accepts either the unanchored `temp/` or anchored `/temp/` form.
+if [ -n "$track_mode" ]; then
+  gi="$project/.gitignore"
+  if ! { [ -f "$gi" ] && { grep -qFx 'temp/' "$gi" || grep -qFx '/temp/' "$gi"; }; }; then
+    {
+      [ -s "$gi" ] && echo ""
+      echo "# Ephemeral working artifacts (throwaway; see working-files.md)"
+      echo "temp/"
+    } >> "$gi"
+  fi
+fi
+
 # Banner.
 echo
 echo "Done."
diff --git a/scripts/sweep-gitignore-tooling.sh b/scripts/sweep-gitignore-tooling.sh
index 68bfe2d..7194d6c 100755
--- a/scripts/sweep-gitignore-tooling.sh
+++ b/scripts/sweep-gitignore-tooling.sh
@@ -153,7 +153,37 @@ for project in "${projects[@]}"; do
   done
 done
 
+# temp/ backfill — mode-independent. Unlike the personal-tooling set above
+# (gitignore-mode only, track-mode deliberately skipped), temp/ holds ephemeral
+# artifacts in every project regardless of whether it tracks its .ai/, so both
+# track- and gitignore-mode projects get it. A separate pass, not an IGNORE_SET
+# member — folding it into that set would miss every track-mode project, which
+# is exactly the set that needs it. working/ is never ignored: it's the tracked
+# home of in-progress work.
+temp_swept=0
+for project in "${projects[@]}"; do
+  [ -d "$project/.git" ] || continue
+  name="$(basename "$project")"
+  gi="$project/.gitignore"
+
+  if [ -f "$gi" ] && { grep -qFx 'temp/' "$gi" || grep -qFx '/temp/' "$gi"; }; then
+    continue
+  fi
+
+  if [ "$dry_run" -eq 1 ]; then
+    echo "DRY   $name — would add: temp/"
+  else
+    {
+      [ -s "$gi" ] && echo ""
+      echo "# Ephemeral working artifacts (throwaway; see working-files.md; swept $(date +%Y-%m-%d))"
+      echo "temp/"
+    } >> "$gi"
+    echo "temp  $name — added: temp/"
+  fi
+  temp_swept=$((temp_swept + 1))
+done
+
 echo
-echo "Summary: $swept swept, $complete already complete, $skipped skipped (of ${#projects[@]} projects)."
+echo "Summary: $swept swept, $complete already complete, $skipped skipped (of ${#projects[@]} projects); $temp_swept temp/ backfilled."
 [ "$dry_run" -eq 1 ] && echo "(dry-run — no files written)"
 exit 0
diff --git a/scripts/tests/install-ai.bats b/scripts/tests/install-ai.bats
index 9c6040c..14f1152 100644
--- a/scripts/tests/install-ai.bats
+++ b/scripts/tests/install-ai.bats
@@ -200,3 +200,39 @@ LAUNCHER="$REAL_REPO/claude-templates/bin/install-ai"
   [ "$status" -eq 0 ]
   [[ "$output" == *"Bootstrap .ai/"* ]]
 }
+
+# --- temp/ ephemeral-artifacts ignore (working/ tracked-from-creation ruling) ---
+
+@test "install-ai --gitignore: ignores temp/ but never working/" {
+  mkdir -p "$TEST_HOME/code/fresh"
+  (cd "$TEST_HOME/code/fresh" && git init -q)
+
+  run bash "$INSTALL_AI" --gitignore "$TEST_HOME/code/fresh"
+
+  [ "$status" -eq 0 ]
+  grep -qFx "temp/" "$TEST_HOME/code/fresh/.gitignore"
+  # working/ is the tracked home of in-progress work — it must never be ignored.
+  ! grep -qEx "/?working/?" "$TEST_HOME/code/fresh/.gitignore"
+}
+
+@test "install-ai --track: ignores temp/ even in track mode" {
+  mkdir -p "$TEST_HOME/code/tracked"
+  (cd "$TEST_HOME/code/tracked" && git init -q)
+
+  run bash "$INSTALL_AI" --track "$TEST_HOME/code/tracked"
+
+  [ "$status" -eq 0 ]
+  # temp/ is ephemeral regardless of whether the project tracks its .ai/ tooling.
+  grep -qFx "temp/" "$TEST_HOME/code/tracked/.gitignore"
+}
+
+@test "install-ai: temp/ ignore is idempotent (not re-added)" {
+  mkdir -p "$TEST_HOME/code/fresh"
+  (cd "$TEST_HOME/code/fresh" && git init -q)
+  printf 'temp/\n' > "$TEST_HOME/code/fresh/.gitignore"
+
+  run bash "$INSTALL_AI" --gitignore "$TEST_HOME/code/fresh"
+
+  [ "$status" -eq 0 ]
+  [ "$(grep -cFx 'temp/' "$TEST_HOME/code/fresh/.gitignore")" -eq 1 ]
+}
diff --git a/scripts/tests/sweep-gitignore-tooling.bats b/scripts/tests/sweep-gitignore-tooling.bats
index f18eac5..240c3be 100644
--- a/scripts/tests/sweep-gitignore-tooling.bats
+++ b/scripts/tests/sweep-gitignore-tooling.bats
@@ -190,3 +190,44 @@ make_project() {
   [ "$status" -eq 0 ]
   [[ "$output" != *"publicly reachable"* ]]
 }
+
+# --- temp/ ephemeral-artifacts backfill (mode-independent) ---
+
+@test "sweep: adds temp/ to a gitignore-mode project" {
+  make_project gimode $'.ai/\n'
+
+  run bash "$SWEEP" "$ROOT"
+
+  [ "$status" -eq 0 ]
+  grep -qFx "temp/" "$ROOT/gimode/.gitignore"
+}
+
+@test "sweep: adds temp/ to a TRACK-mode project too (temp/ is mode-independent)" {
+  make_project trackmode $'# build\nout/\n'
+
+  run bash "$SWEEP" "$ROOT"
+
+  [ "$status" -eq 0 ]
+  # The tooling set is skipped in track mode, but temp/ is not.
+  grep -qFx "temp/" "$ROOT/trackmode/.gitignore"
+  ! grep -qFx ".ai/" "$ROOT/trackmode/.gitignore"
+}
+
+@test "sweep: never adds working/" {
+  make_project gimode $'.ai/\n'
+
+  run bash "$SWEEP" "$ROOT"
+
+  [ "$status" -eq 0 ]
+  ! grep -qEx "/?working/?" "$ROOT/gimode/.gitignore"
+}
+
+@test "sweep: temp/ backfill is idempotent" {
+  make_project gimode $'.ai/\ntemp/\n'
+  bash "$SWEEP" "$ROOT" >/dev/null
+
+  run bash "$SWEEP" "$ROOT"
+
+  [ "$status" -eq 0 ]
+  [ "$(grep -cFx 'temp/' "$ROOT/gimode/.gitignore")" -eq 1 ]
+}