diff --git a/docs/development/current/main/phases/phase-131/README.md b/docs/development/current/main/phases/phase-131/README.md
index 53d8ec61..c09f1c98 100644
--- a/docs/development/current/main/phases/phase-131/README.md
+++ b/docs/development/current/main/phases/phase-131/README.md
@@ -58,6 +58,69 @@ y = x + 2
 return y
 ```
 
+## Task 3 & 4: smokes Runner Improvements (DONE)
+
+### Task 3: OutputContract 統一
+
+**実装箇所**: `tools/smokes/v2/lib/llvm_exe_runner.sh`
+
+**新しい統一インターフェース**:
+```bash
+check_output_contract() {
+    local contract_type=$1  # "exit_code" / "numeric" / "substring"
+    local expected=$2
+    local actual=$3
+    local context=$4        # (optional) Context description
+
+    # 統一された検証ロジック
+}
+```
+
+**利点**:
+- ✅ exit_code/numeric/substring が統一インターフェース
+- ✅ エラーメッセージが一貫している
+- ✅ コピペコードが削減（約30行の整理）
+- ✅ 既存 smoke 全て PASS（後方互換性）
+
+**変更箇所**:
+- `llvm_exe_build_and_run_numeric_smoke`: numeric 検証を統一インターフェース化
+- `llvm_exe_build_and_run_expect_exit_code`: exit_code 検証を統一インターフェース化
+
+### Task 4: require_joinir_dev ヘルパー
+
+**実装箇所**:
+- `tools/smokes/v2/lib/llvm_exe_runner.sh`
+- `tools/smokes/v2/lib/test_runner.sh`
+
+**新しいヘルパー関数**:
+```bash
+require_joinir_dev() {
+    export NYASH_JOINIR_DEV=1
+    export HAKO_JOINIR_STRICT=1
+    echo "[INFO] JoinIR dev mode enabled (...)"
+}
+```
+
+**利点**:
+- ✅ 環境変数セットアップが一元化
+- ✅ dev-only fixture が統一パターンで記述可能
+- ✅ コピペ防止（3行→1行）
+- ✅ 既存 smoke 全て PASS
+
+**使用例**:
+```bash
+# Before (phase131_loop_true_break_once_llvm_exe.sh)
+export NYASH_JOINIR_DEV=1
+export HAKO_JOINIR_STRICT=1
+
+# After
+require_joinir_dev
+```
+
+**適用済み箇所**:
+- `tools/smokes/v2/profiles/integration/apps/phase131_loop_true_break_once_llvm_exe.sh`
+- `tools/smokes/v2/profiles/integration/apps/phase131_loop_true_break_once_vm.sh`
+
 ## SSOT Contracts
 
 ### EnvLayout (Phase 126)
diff --git a/tools/build_llvm.sh b/tools/build_llvm.sh
index 50c56b90..8dd47f29 100644
--- a/tools/build_llvm.sh
+++ b/tools/build_llvm.sh
@@ -51,7 +51,9 @@ CARGO_TARGET_DIR_EFFECTIVE="${CARGO_TARGET_DIR:-$PWD/target}"
 # folder so rustc can atomically persist artifacts without cross-device rename issues.
 #
 # NOTE: release/deps may not exist yet on first build, so create it eagerly.
-TMPDIR_EFFECTIVE="${TMPDIR:-$CARGO_TARGET_DIR_EFFECTIVE/release/deps}"
+# TMPDIR configuration (SSOT: tools/smokes/v2/lib/env.sh sets TARGET_TMPDIR)
+# Use TARGET_TMPDIR if set by smoke framework, otherwise fallback to cargo deps dir
+TMPDIR_EFFECTIVE="${TMPDIR:-${TARGET_TMPDIR:-$CARGO_TARGET_DIR_EFFECTIVE/release/deps}}"
 mkdir -p "$TMPDIR_EFFECTIVE"
 export TMPDIR="$TMPDIR_EFFECTIVE"