diff --git a/.gitignore b/.gitignore
index 7595ee1..30293c8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -157,4 +157,7 @@ $RECYCLE.BIN/
 
 # コンパイル関係
 core/bin/*
-selfhost/bin/*
\ No newline at end of file
+selfhost/bin/*
+
+# Claude Code
+nul
\ No newline at end of file
diff --git a/AGENTS.md b/AGENTS.md
new file mode 100644
index 0000000..9b05ab9
--- /dev/null
+++ b/AGENTS.md
@@ -0,0 +1,78 @@
+# プロジェクト概要
+
+I-TTS (Integration TTS) はDiscord用の読み上げBOT。VOICEVOX、COEIROINK、SHAREVOX、VoiceTextなどの音声合成APIに対応。
+
+# ビルドコマンド
+
+```bash
+# ビルド (テストとCheckstyle含む)
+./gradlew build
+
+# テストのみ
+./gradlew test
+
+# 特定モジュールのテスト
+./gradlew :core:test
+./gradlew :selfhost:test
+
+# 単一テストクラス実行
+./gradlew :core:test --tests "dev.felnull.itts.core.savedata.repository.BotStateDataTest"
+
+# Checkstyleのみ
+./gradlew checkstyleMain
+
+# Shadow JAR作成 (実行可能JAR)
+./gradlew :selfhost:shadowJar
+```
+
+成果物は `selfhost/build/libs/itts-selfhost-{version}.jar` に生成される。
+
+# アーキテクチャ
+
+## モジュール構成
+
+- **core**: BOTのコアロジック。JDAやLavaPlayerを使用したDiscord連携、音声合成、データ永続化
+- **selfhost**: セルフホスト用エントリポイント。設定ファイル読み込みとランタイムコンテキスト提供
+
+## マネージャーパターン
+
+`ITTSRuntime`がシングルトンとして各マネージャーを保持:
+- `ConfigManager`: 設定管理
+- `VoiceManager`: 音声タイプ管理
+- `TTSManager`: テキスト読み上げ処理
+- `DictionaryManager`: 辞書管理
+- `CacheManager`: 音声キャッシュ
+- `SaveDataManager`: データ永続化
+
+## 音声合成 (voice パッケージ)
+
+抽象化レイヤー:
+- `VoiceType`: 音声合成エンジン種別 (VOICEVOX, COEIROINK等)
+- `VoiceCategory`: エンジン内のキャラクター
+- `Voice`: 具体的な声スタイル
+
+各エンジン実装は `voice.voicevox`, `voice.coeiroink`, `voice.voicetext` サブパッケージに配置。
+
+## データ永続化 (savedata パッケージ)
+
+- **dao**: データアクセスオブジェクト。SQLite/MySQL対応
+- **repository**: ビジネスロジック向けリポジトリ層
+- **legacy**: 旧バージョンデータ移行
+
+スキーマ定義は [docs/schema-sqlite.md](docs/schema-sqlite.md) を参照。
+
+## Discordコマンド (discord.command パッケージ)
+
+`BaseCommand`を継承してスラッシュコマンドを実装。主要コマンド:
+- `JoinCommand`, `LeaveCommand`: VC参加/退出
+- `VoiceCommand`: 音声タイプ変更
+- `DictCommand`: 辞書管理
+- `ConfigCommand`: サーバー設定
+
+# コードスタイル
+
+Checkstyle (`config/checkstyle/checkstyle.xml`) で強制:
+- `var` 禁止 (明示的な型宣言必須)
+- 全publicメソッド/フィールドにJavadoc必須
+- 行長170文字以内
+- タブ文字禁止
diff --git a/CHANGELOG.md b/CHANGELOG.md
index dc460c9..3215ab1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,13 +8,14 @@
 ### Added
 
 ### Changed
-
+- IANAのTLDリストを参照してドメイン省略するように変更
 ### Deprecated
 
 ### Removed
 
 ### Fixed
-
+- 多数の不備を修正
+- 辞書登録のバリデーションを強化
 ### Security
 
 ## [2.1.0] - 2026-02-11
diff --git a/CLAUDE.md b/CLAUDE.md
new file mode 120000
index 0000000..47dc3e3
--- /dev/null
+++ b/CLAUDE.md
@@ -0,0 +1 @@
+AGENTS.md
\ No newline at end of file
diff --git a/core/build.gradle.kts b/core/build.gradle.kts
index 32f6aa4..41a51b2 100644
--- a/core/build.gradle.kts
+++ b/core/build.gradle.kts
@@ -18,17 +18,17 @@ dependencies {
     testRuntimeOnly("org.junit.platform:junit-platform-launcher")
     testImplementation("org.mockito:mockito-junit-jupiter:5.21.0")
 
-    api("net.dv8tion:JDA:6.3.0")
+    api("net.dv8tion:JDA:6.3.2")
     api("org.apache.commons:commons-lang3:3.20.0")
     api("com.google.code.gson:gson:2.13.2")
     api("com.google.guava:guava:33.5.0-jre")
     api("dev.felnull:felnull-java-library:1.75")
     api("dev.arbjerg:lavaplayer:2.2.6")
     api("club.minnced:jdave-api:0.1.5")
-    runtimeOnly("club.minnced:jdave-native-linux-x86-64:0.1.5")
-    runtimeOnly("club.minnced:jdave-native-linux-aarch64:0.1.5")
-    runtimeOnly("club.minnced:jdave-native-win-x86-64:0.1.5")
-    runtimeOnly("club.minnced:jdave-native-darwin:0.1.5")
+    runtimeOnly("club.minnced:jdave-native-linux-x86-64:0.1.7")
+    runtimeOnly("club.minnced:jdave-native-linux-aarch64:0.1.7")
+    runtimeOnly("club.minnced:jdave-native-win-x86-64:0.1.7")
+    runtimeOnly("club.minnced:jdave-native-darwin:0.1.7")
     api("commons-io:commons-io:2.20.0")
     api("com.ibm.icu:icu4j:77.1")
     api("com.atilika.kuromoji:kuromoji-ipadic:0.9.0")
diff --git a/core/src/main/java/dev/felnull/itts/core/ITTSRuntime.java b/core/src/main/java/dev/felnull/itts/core/ITTSRuntime.java
index 16259b0..2142575 100644
--- a/core/src/main/java/dev/felnull/itts/core/ITTSRuntime.java
+++ b/core/src/main/java/dev/felnull/itts/core/ITTSRuntime.java
@@ -5,6 +5,7 @@
 import dev.felnull.itts.core.cache.CacheManager;
 import dev.felnull.itts.core.config.ConfigManager;
 import dev.felnull.itts.core.dict.DictionaryManager;
+import dev.felnull.itts.core.dict.DomainListManager;
 import dev.felnull.itts.core.discord.Bot;
 import dev.felnull.itts.core.savedata.SaveDataManager;
 import dev.felnull.itts.core.tts.TTSManager;
@@ -99,6 +100,11 @@ public class ITTSRuntime {
      */
     private final VoiceAudioManager voiceAudioManager = new VoiceAudioManager();
 
+    /**
+     * ドメイン名リストマネージャー
+     */
+    private final DomainListManager domainListManager = new DomainListManager();
+
     /**
      * 辞書マネージャー
      */
@@ -148,7 +154,7 @@ private ITTSRuntime(ITTSRuntimeContext runtimeContext) {
         this.configManager = new ConfigManager(runtimeContext.getConfigContext());
         this.cacheManager = new CacheManager(runtimeContext.getGlobalCacheAccessFactory());
 
-        this.managers = ImmutableList.of(configManager, voiceManager);
+        this.managers = ImmutableList.of(configManager, voiceManager, domainListManager);
     }
 
     /**
@@ -265,6 +271,9 @@ public DictionaryManager getDictionaryManager() {
         return dictionaryManager;
     }
 
+    public DomainListManager getDomainListManager() {
+        return domainListManager;
+    }
 
     public ITTSNetworkManager getNetworkManager() {
         return networkManager;
diff --git a/core/src/main/java/dev/felnull/itts/core/ITTSRuntimeUse.java b/core/src/main/java/dev/felnull/itts/core/ITTSRuntimeUse.java
index 8c7c8f3..28208bb 100644
--- a/core/src/main/java/dev/felnull/itts/core/ITTSRuntimeUse.java
+++ b/core/src/main/java/dev/felnull/itts/core/ITTSRuntimeUse.java
@@ -4,6 +4,7 @@
 import dev.felnull.itts.core.cache.CacheManager;
 import dev.felnull.itts.core.config.ConfigManager;
 import dev.felnull.itts.core.dict.DictionaryManager;
+import dev.felnull.itts.core.dict.DomainListManager;
 import dev.felnull.itts.core.discord.Bot;
 import dev.felnull.itts.core.tts.TTSManager;
 import dev.felnull.itts.core.voice.VoiceManager;
@@ -63,6 +64,10 @@ default DictionaryManager getDictionaryManager() {
         return getITTSRuntime().getDictionaryManager();
     }
 
+    default DomainListManager getDomainListManager() {
+        return getITTSRuntime().getDomainListManager();
+    }
+
     default VoiceManager getVoiceManager() {
         return getITTSRuntime().getVoiceManager();
     }
diff --git a/core/src/main/java/dev/felnull/itts/core/dict/AbbreviationDictionary.java b/core/src/main/java/dev/felnull/itts/core/dict/AbbreviationDictionary.java
index f6acf91..0cb467b 100644
--- a/core/src/main/java/dev/felnull/itts/core/dict/AbbreviationDictionary.java
+++ b/core/src/main/java/dev/felnull/itts/core/dict/AbbreviationDictionary.java
@@ -29,11 +29,11 @@ public class AbbreviationDictionary implements Dictionary {
                 Matcher matcher = pattern.matcher(s);
                 return matcher.find();
             })*/
-            .addOption(1, "ドメインショウリャク", s -> {
+            /*.addOption(1, "ドメインショウリャク", s -> {
                 Pattern pattern = Pattern.compile("^([a-zA-Z0-9][a-zA-Z0-9-]*[a-zA-Z0-9]*\\.)+[a-zA-Z]{2,}$");
                 Matcher matcher = pattern.matcher(s);
                 return matcher.find();
-            })
+            })*/
             .addOption(1, "アイピーブイフォーショウリャク", s -> {
                 Pattern pattern = Pattern.compile("^((25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])\\.){3}(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])$");
                 Matcher matcher = pattern.matcher(s);
@@ -61,9 +61,15 @@ public class AbbreviationDictionary implements Dictionary {
      */
     private final URLReplacer urlReplacer = new URLReplacer("ユーアルエルショウリャク");
 
+    /**
+     * ドメインリプレーサー
+     */
+    private final DomainReplacer domainReplacer = new DomainReplacer("ドメインショウリャク");
+
     @Override
     public @NotNull String apply(@NotNull String text, long guildId) {
         text = urlReplacer.replace(text);
+        text = domainReplacer.replace(text);
         text = CODE_BLOCK_REGEX.matcher(text).replaceAll("コードブロックショウリャク");
         return regexUtil.replaceText(text);
     }
diff --git a/core/src/main/java/dev/felnull/itts/core/dict/DictionaryManager.java b/core/src/main/java/dev/felnull/itts/core/dict/DictionaryManager.java
index 64ad2b6..3efd810 100644
--- a/core/src/main/java/dev/felnull/itts/core/dict/DictionaryManager.java
+++ b/core/src/main/java/dev/felnull/itts/core/dict/DictionaryManager.java
@@ -8,6 +8,7 @@
 import dev.felnull.itts.core.savedata.legacy.LegacyDictData;
 import dev.felnull.itts.core.savedata.legacy.LegacySaveDataLayer;
 import dev.felnull.itts.core.util.JsonUtils;
+import dev.felnull.itts.core.util.PatternValidator;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.annotations.Unmodifiable;
@@ -28,6 +29,16 @@ public class DictionaryManager implements ITTSRuntimeUse {
      */
     private static final int FILE_VERSION = 0;
 
+    /**
+     * アップロード時の最大エントリ数
+     */
+    private static final int MAX_DICT_ENTRIES = 1000;
+
+    /**
+     * エントリの最大文字数
+     */
+    private static final int MAX_TEXT_LENGTH = 1000;
+
     /**
      * グローバル辞書
      */
@@ -254,35 +265,55 @@ public List<LegacyDictData> serverDictLoadFromJson(@NotNull JsonObject jo, long
         int version = JsonUtils.getInt(jo, "version", -1);
 
         if (version != FILE_VERSION) {
-            throw new RuntimeException("Unsupported dictionary file version.");
+            throw new RuntimeException("Unsupported dictionary file version");
+        }
+
+        JsonElement entryElement = jo.get("entry");
+        if (entryElement == null || !entryElement.isJsonObject()) {
+            throw new RuntimeException("Invalid dictionary file format");
+        }
+
+        JsonObject entry = jo.getAsJsonObject("entry");
+
+        if (entry.size() > MAX_DICT_ENTRIES) {
+            throw new RuntimeException("Dictionary entry count exceeds limit. Maximum is " + MAX_DICT_ENTRIES);
         }
 
-        if (jo.get("entry").isJsonObject()) {
-            JsonObject entry = jo.getAsJsonObject("entry");
-            LegacySaveDataLayer legacySaveDataLayer = SaveDataManager.getInstance().getLegacySaveDataLayer();
+        LegacySaveDataLayer legacySaveDataLayer = SaveDataManager.getInstance().getLegacySaveDataLayer();
+
+        for (Map.Entry<String, JsonElement> en : entry.entrySet()) {
+            String target = en.getKey();
+
+            if (!en.getValue().isJsonPrimitive() || !en.getValue().getAsJsonPrimitive().isString()) {
+                continue;
+            }
+
+            String read = en.getValue().getAsString();
 
-            for (Map.Entry<String, JsonElement> en : entry.entrySet()) {
-                String target = en.getKey();
+            if (target.length() > MAX_TEXT_LENGTH || read.length() > MAX_TEXT_LENGTH) {
+                continue;
+            }
 
-                if (!en.getValue().isJsonPrimitive() || !en.getValue().getAsJsonPrimitive().isString()) {
-                    continue;
-                }
+            if (target.isBlank() || read.isBlank()) {
+                continue;
+            }
 
-                String read = en.getValue().getAsString();
+            if (!PatternValidator.validate(target).valid()) {
+                continue;
+            }
 
-                LegacyDictData pre = legacySaveDataLayer.getServerDictData(guildId, target);
+            LegacyDictData pre = legacySaveDataLayer.getServerDictData(guildId, target);
 
-                if (!overwrite && pre != null) {
-                    continue;
-                }
+            if (!overwrite && pre != null) {
+                continue;
+            }
 
-                legacySaveDataLayer.addServerDictData(guildId, target, read);
+            legacySaveDataLayer.addServerDictData(guildId, target, read);
 
-                LegacyDictData ndata = Objects.requireNonNull(legacySaveDataLayer.getServerDictData(guildId, target));
+            LegacyDictData ndata = Objects.requireNonNull(legacySaveDataLayer.getServerDictData(guildId, target));
 
-                if (!ndata.equals(pre)) {
-                    ret.add(ndata);
-                }
+            if (!ndata.equals(pre)) {
+                ret.add(ndata);
             }
         }
 
diff --git a/core/src/main/java/dev/felnull/itts/core/dict/DomainListManager.java b/core/src/main/java/dev/felnull/itts/core/dict/DomainListManager.java
new file mode 100644
index 0000000..63feaa2
--- /dev/null
+++ b/core/src/main/java/dev/felnull/itts/core/dict/DomainListManager.java
@@ -0,0 +1,64 @@
+package dev.felnull.itts.core.dict;
+
+import dev.felnull.itts.core.ITTSBaseManager;
+import java.io.IOException;
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.util.concurrent.CompletableFuture;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * TLDリストマネージャー
+ **/
+
+public class DomainListManager implements ITTSBaseManager {
+
+    /**
+     *  取得先URL
+     */
+    private static final URI IANA_DATA_URI = URI.create("https://data.iana.org/TLD/tlds-alpha-by-domain.txt");
+
+    /**
+     * 読み込み済みTLDリスト
+     */
+    private Pattern domainPattern;
+
+    @Override
+    public @NotNull CompletableFuture<?> init() {
+        return CompletableFuture.runAsync(() -> {
+            try {
+                HttpClient hc = getNetworkManager().getHttpClient();
+                HttpRequest request = HttpRequest.newBuilder().uri(IANA_DATA_URI).GET().build();
+
+                HttpResponse<String> res = hc.send(request, HttpResponse.BodyHandlers.ofString());
+
+                String processedDomains = res.body().lines()
+                    .filter(line -> !line.startsWith("#"))
+                    .filter(list -> !list.isBlank())
+                    .map(String::trim)
+                    .map(String::toLowerCase)
+                    .map(Pattern::quote)
+                    .collect(Collectors.joining("|"));
+
+                String regex = "\\b[a-zA-Z0-9.-]+\\.(?i:" + processedDomains + ")\\b";
+                domainPattern = Pattern.compile(regex);
+            } catch (IOException | InterruptedException e) {
+                getITTSLogger().error("failed to get domain list.");
+            }
+        }, getAsyncExecutor());
+    }
+
+    /**
+     *  読み込み済みTLDゲッター
+     *
+     * @return ドメイン検知正規表現
+     */
+    public @Nullable Pattern getPattern() {
+        return domainPattern;
+    }
+}
diff --git a/core/src/main/java/dev/felnull/itts/core/dict/DomainReplacer.java b/core/src/main/java/dev/felnull/itts/core/dict/DomainReplacer.java
new file mode 100644
index 0000000..b8934a3
--- /dev/null
+++ b/core/src/main/java/dev/felnull/itts/core/dict/DomainReplacer.java
@@ -0,0 +1,39 @@
+package dev.felnull.itts.core.dict;
+
+import dev.felnull.itts.core.ITTSRuntimeUse;
+import java.util.regex.Pattern;
+
+/**
+ * ドメインを置き換える処理
+ */
+public class DomainReplacer implements ITTSRuntimeUse {
+
+    /**
+     * 置き換えるテキスト
+     */
+    private final String replacedText;
+
+    /**
+     * コンストラクタ
+     *
+     * @param replacedText 置き換えるテキスト
+     */
+    public DomainReplacer(String replacedText) {
+        this.replacedText = replacedText;
+    }
+
+    /**
+     * テキスト置き換え
+     *
+     * @param text テキスト
+     * @return 置き換えられたテキスト
+     */
+    public String replace(String text) {
+        Pattern domainPattern = getDomainListManager().getPattern();
+        if (domainPattern != null) {
+            return domainPattern.matcher(text).replaceAll(replacedText);
+        }
+
+        return text;
+    }
+}
diff --git a/core/src/main/java/dev/felnull/itts/core/dict/GlobalDictionary.java b/core/src/main/java/dev/felnull/itts/core/dict/GlobalDictionary.java
index 833b012..e8fbcd3 100644
--- a/core/src/main/java/dev/felnull/itts/core/dict/GlobalDictionary.java
+++ b/core/src/main/java/dev/felnull/itts/core/dict/GlobalDictionary.java
@@ -11,7 +11,9 @@
 import java.util.Map;
 import java.util.function.Function;
 import java.util.regex.Pattern;
+import java.util.regex.PatternSyntaxException;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 /**
  * グローバル辞書
@@ -50,7 +52,15 @@ public int getDefaultPriority() {
     protected @NotNull Map<Pattern, Function<String, String>> getReplaces(long guildId) {
         LegacySaveDataLayer legacySaveDataLayer = SaveDataManager.getInstance().getLegacySaveDataLayer();
         return legacySaveDataLayer.getAllGlobalDictData().stream()
-                .map(n -> Pair.of(Pattern.compile(n.getTarget()), n.getRead()))
+                .flatMap(n -> {
+                    try {
+                        Pattern pattern = Pattern.compile(n.getTarget());
+                        return Stream.of(Pair.of(pattern, n.getRead()));
+                    } catch (PatternSyntaxException e) {
+                        getITTSLogger().warn("Invalid regex pattern in global dict: {}", n.getTarget());
+                        return Stream.empty();
+                    }
+                })
                 .collect(Collectors.toMap(Pair::getLeft, patternStringPair -> n -> patternStringPair.getRight()));
     }
 }
diff --git a/core/src/main/java/dev/felnull/itts/core/dict/ServerDictionary.java b/core/src/main/java/dev/felnull/itts/core/dict/ServerDictionary.java
index cbd01ed..5f2b79c 100644
--- a/core/src/main/java/dev/felnull/itts/core/dict/ServerDictionary.java
+++ b/core/src/main/java/dev/felnull/itts/core/dict/ServerDictionary.java
@@ -11,7 +11,9 @@
 import java.util.Map;
 import java.util.function.Function;
 import java.util.regex.Pattern;
+import java.util.regex.PatternSyntaxException;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 /**
  * サーバー辞書
@@ -50,7 +52,15 @@ public int getDefaultPriority() {
     protected @NotNull Map<Pattern, Function<String, String>> getReplaces(long guildId) {
         LegacySaveDataLayer legacySaveDataLayer = SaveDataManager.getInstance().getLegacySaveDataLayer();
         return legacySaveDataLayer.getAllServerDictData(guildId).stream()
-                .map(n -> Pair.of(Pattern.compile(n.getTarget()), n.getRead()))
+                .flatMap(n -> {
+                    try {
+                        Pattern pattern = Pattern.compile(n.getTarget());
+                        return Stream.of(Pair.of(pattern, n.getRead()));
+                    } catch (PatternSyntaxException e) {
+                        getITTSLogger().warn("Invalid regex pattern in server dict: {}", n.getTarget());
+                        return Stream.empty();
+                    }
+                })
                 .collect(Collectors.toMap(Pair::getLeft, patternStringPair -> n -> patternStringPair.getRight()));
     }
 }
diff --git a/core/src/main/java/dev/felnull/itts/core/discord/DCEventListener.java b/core/src/main/java/dev/felnull/itts/core/discord/DCEventListener.java
index f613c12..1eca8ac 100644
--- a/core/src/main/java/dev/felnull/itts/core/discord/DCEventListener.java
+++ b/core/src/main/java/dev/felnull/itts/core/discord/DCEventListener.java
@@ -48,6 +48,10 @@ public void onCommandAutoCompleteInteraction(@NotNull CommandAutoCompleteInterac
 
     @Override
     public void onMessageReceived(@NotNull MessageReceivedEvent event) {
+        if (!event.isFromGuild()) {
+            return;
+        }
+
         if (getTTSManager().canSpeak(event.getGuild())) {
             getTTSManager().sayChat(event.getGuild(), event.getChannel(), event.getMember(), event.getMessage());
             getTTSManager().sayUploadFile(event.getGuild(), event.getChannel(), event.getMember(), event.getMessage().getAttachments());
diff --git a/core/src/main/java/dev/felnull/itts/core/discord/command/AdminCommand.java b/core/src/main/java/dev/felnull/itts/core/discord/command/AdminCommand.java
index eef3812..5be6950 100644
--- a/core/src/main/java/dev/felnull/itts/core/discord/command/AdminCommand.java
+++ b/core/src/main/java/dev/felnull/itts/core/discord/command/AdminCommand.java
@@ -79,6 +79,8 @@ private void vnick(SlashCommandInteractionEvent event) {
         if (name == null) {
             sud.setNickName(null);
             event.reply(DiscordUtils.getEscapedName(event.getGuild(), user) + "の読み上げユーザ名をリセットしました。").queue();
+        } else if (name.isBlank()) {
+            event.reply("名前を空にすることはできません。リセットするには名前を指定せずに実行してください。").setEphemeral(true).queue();
         } else {
             sud.setNickName(name);
             event.reply(DiscordUtils.getEscapedName(event.getGuild(), user) + "の読み上げユーザ名を変更しました。").queue();
diff --git a/core/src/main/java/dev/felnull/itts/core/discord/command/ConfigCommand.java b/core/src/main/java/dev/felnull/itts/core/discord/command/ConfigCommand.java
index 3ae0e01..d1e0415 100644
--- a/core/src/main/java/dev/felnull/itts/core/discord/command/ConfigCommand.java
+++ b/core/src/main/java/dev/felnull/itts/core/discord/command/ConfigCommand.java
@@ -5,6 +5,7 @@
 import dev.felnull.itts.core.savedata.legacy.LegacySaveDataLayer;
 import dev.felnull.itts.core.savedata.legacy.LegacyServerData;
 import dev.felnull.itts.core.savedata.repository.ServerData;
+import dev.felnull.itts.core.util.PatternValidator;
 import dev.felnull.itts.core.voice.VoiceCategory;
 import dev.felnull.itts.core.voice.VoiceManager;
 import dev.felnull.itts.core.voice.VoiceType;
@@ -171,6 +172,13 @@ private void readIgnore(SlashCommandInteractionEvent event) {
         Guild guild = Objects.requireNonNull(event.getGuild());
 
         String op = Objects.requireNonNull(event.getOption("regex", OptionMapping::getAsString));
+
+        PatternValidator.ValidationResult validationResult = PatternValidator.validate(op);
+        if (!validationResult.valid()) {
+            event.reply(validationResult.error()).setEphemeral(true).queue();
+            return;
+        }
+
         LegacySaveDataLayer legacySaveDataLayer = SaveDataManager.getInstance().getLegacySaveDataLayer();
         LegacyServerData sd = legacySaveDataLayer.getServerData(guild.getIdLong());
 
diff --git a/core/src/main/java/dev/felnull/itts/core/discord/command/DenyCommand.java b/core/src/main/java/dev/felnull/itts/core/discord/command/DenyCommand.java
index 5c2f9e8..68a9061 100644
--- a/core/src/main/java/dev/felnull/itts/core/discord/command/DenyCommand.java
+++ b/core/src/main/java/dev/felnull/itts/core/discord/command/DenyCommand.java
@@ -92,7 +92,6 @@ private void show(SlashCommandInteractionEvent event) {
             return;
         }
 
-        MessageCreateBuilder msg = new MessageCreateBuilder().addContent("読み上げ拒否されたユーザ一覧\n");
         StringBuilder sb = new StringBuilder();
 
         JDA jda = event.getJDA();
@@ -103,7 +102,15 @@ private void show(SlashCommandInteractionEvent event) {
                 sb.append(DiscordUtils.getEscapedName(guild, user)).append("\n");
             }
         }
-        msg.addContent("``" + sb + "``");
+
+        if (sb.isEmpty()) {
+            event.reply("読み上げ拒否されたユーザの情報を取得できませんでした。").setEphemeral(true).queue();
+            return;
+        }
+
+        MessageCreateBuilder msg = new MessageCreateBuilder()
+                .addContent("読み上げ拒否されたユーザ一覧\n")
+                .addContent("```\n" + sb + "```");
         event.reply(msg.build()).setEphemeral(true).queue();
     }
 
diff --git a/core/src/main/java/dev/felnull/itts/core/discord/command/DictCommand.java b/core/src/main/java/dev/felnull/itts/core/discord/command/DictCommand.java
index 142fc76..52230db 100644
--- a/core/src/main/java/dev/felnull/itts/core/discord/command/DictCommand.java
+++ b/core/src/main/java/dev/felnull/itts/core/discord/command/DictCommand.java
@@ -3,12 +3,14 @@
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import com.google.gson.JsonObject;
+import com.google.gson.JsonSyntaxException;
 import dev.felnull.itts.core.dict.Dictionary;
 import dev.felnull.itts.core.dict.DictionaryManager;
 import dev.felnull.itts.core.dict.ServerDictionary;
 import dev.felnull.itts.core.savedata.SaveDataManager;
 import dev.felnull.itts.core.savedata.legacy.LegacyDictData;
 import dev.felnull.itts.core.savedata.legacy.LegacySaveDataLayer;
+import dev.felnull.itts.core.util.PatternValidator;
 import dev.felnull.itts.core.util.StringUtils;
 import net.dv8tion.jda.api.EmbedBuilder;
 import net.dv8tion.jda.api.entities.Guild;
@@ -54,6 +56,11 @@ public class DictCommand extends BaseCommand {
      */
     private static final int MAX_FIELD_TEXT_LENGTH = 125;
 
+    /**
+     * アップロードファイルの最大サイズ (1MB)
+     */
+    private static final int MAX_UPLOAD_FILE_SIZE = 1024 * 1024;
+
     /**
      * GSOUN
      */
@@ -175,11 +182,24 @@ private void upload(SlashCommandInteractionEvent event) {
         Message.Attachment file = Objects.requireNonNull(event.getOption("file", OptionMapping::getAsAttachment));
         boolean overwrite = Objects.requireNonNull(event.getOption("overwrite", OptionMapping::getAsBoolean));
 
+        if (file.getSize() > MAX_UPLOAD_FILE_SIZE) {
+            int maxSizeMB = MAX_UPLOAD_FILE_SIZE / (1024 * 1024);
+            event.reply(String.format("ファイルサイズが大きすぎます。最大%dMBまでです。", maxSizeMB)).setEphemeral(true).queue();
+            return;
+        }
+
         event.deferReply().queue();
 
         file.getProxy().download().thenApplyAsync(stream -> {
-            try (InputStream st = new BufferedInputStream(stream); Reader reader = new InputStreamReader(st)) {
-                return GSON.fromJson(reader, JsonObject.class);
+            try (InputStream st = new BufferedInputStream(stream);
+                 Reader reader = new InputStreamReader(st, StandardCharsets.UTF_8)) {
+                JsonObject result = GSON.fromJson(reader, JsonObject.class);
+                if (result == null) {
+                    throw new RuntimeException("Invalid JSON file");
+                }
+                return result;
+            } catch (JsonSyntaxException e) {
+                throw new RuntimeException("Invalid JSON format: " + e.getMessage());
             } catch (IOException e) {
                 throw new RuntimeException(e);
             }
@@ -204,7 +224,8 @@ private void upload(SlashCommandInteractionEvent event) {
                 event.getHook().sendMessageEmbeds(replayEmbedBuilder.build()).addContent(overwrite ? "以下の単語の読みを上書き登録しました" : "以下の単語の読みを登録しました").queue();
             } else {
                 getITTSLogger().error("Dictionary registration failure", error);
-                event.getHook().sendMessage("辞書ファイルの読み込み中にエラーが発生しました").queue();
+                String errorMessage = error.getCause() != null ? error.getCause().getMessage() : error.getMessage();
+                event.getHook().sendMessage("辞書ファイルの読み込み中にエラーが発生しました: " + errorMessage).queue();
             }
         }, getAsyncExecutor());
 
@@ -266,8 +287,19 @@ private void add(SlashCommandInteractionEvent event) {
         String word = Objects.requireNonNull(event.getOption("word", OptionMapping::getAsString));
         String reading = Objects.requireNonNull(event.getOption("reading", OptionMapping::getAsString));
 
+        if (word.isBlank() || reading.isBlank()) {
+            event.reply("単語と読みを空にすることはできません。").setEphemeral(true).queue();
+            return;
+        }
+
         if (word.length() > MAX_TEXT_LENGTH || reading.length() > MAX_TEXT_LENGTH) {
-            event.reply(String.format("登録可能な最大文字数は%d文字です", MAX_TEXT_LENGTH)).queue();
+            event.reply(String.format("登録可能な最大文字数は%d文字です", MAX_TEXT_LENGTH)).setEphemeral(true).queue();
+            return;
+        }
+
+        PatternValidator.ValidationResult validationResult = PatternValidator.validate(word);
+        if (!validationResult.valid()) {
+            event.reply(validationResult.error()).setEphemeral(true).queue();
             return;
         }
 
diff --git a/core/src/main/java/dev/felnull/itts/core/discord/command/VnickCommand.java b/core/src/main/java/dev/felnull/itts/core/discord/command/VnickCommand.java
index c5aa5e0..9788909 100644
--- a/core/src/main/java/dev/felnull/itts/core/discord/command/VnickCommand.java
+++ b/core/src/main/java/dev/felnull/itts/core/discord/command/VnickCommand.java
@@ -51,6 +51,8 @@ public void commandInteraction(SlashCommandInteractionEvent event) {
         if (name == null) {
             sud.setNickName(null);
             event.reply("自分の読み上げユーザ名をリセットしました。").setEphemeral(true).queue();
+        } else if (name.isBlank()) {
+            event.reply("名前を空にすることはできません。リセットするには名前を指定せずに実行してください。").setEphemeral(true).queue();
         } else {
             sud.setNickName(name);
             event.reply("自分の読み上げユーザ名を変更しました。").setEphemeral(true).queue();
diff --git a/core/src/main/java/dev/felnull/itts/core/tts/TTSManager.java b/core/src/main/java/dev/felnull/itts/core/tts/TTSManager.java
index 3f7bc75..0228610 100644
--- a/core/src/main/java/dev/felnull/itts/core/tts/TTSManager.java
+++ b/core/src/main/java/dev/felnull/itts/core/tts/TTSManager.java
@@ -24,6 +24,7 @@
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Function;
 import java.util.regex.Pattern;
+import java.util.regex.PatternSyntaxException;
 
 /**
  * TTS管理
@@ -186,9 +187,13 @@ public void sayChat(@NotNull Guild guild, @NotNull MessageChannel messageChannel
 
         String ignoreRegex = legacySaveDataLayer.getServerData(guild.getIdLong()).getIgnoreRegex();
         if (ignoreRegex != null) {
-            Pattern ignorePattern = Pattern.compile(ignoreRegex);
-            if (ignorePattern.matcher(message.getContentDisplay()).matches()) {
-                return;
+            try {
+                Pattern ignorePattern = Pattern.compile(ignoreRegex);
+                if (ignorePattern.matcher(message.getContentDisplay()).matches()) {
+                    return;
+                }
+            } catch (PatternSyntaxException e) {
+                getITTSLogger().warn("Invalid ignore regex for guild {}: {}", guild.getIdLong(), ignoreRegex);
             }
         }
 
diff --git a/core/src/main/java/dev/felnull/itts/core/util/PatternValidator.java b/core/src/main/java/dev/felnull/itts/core/util/PatternValidator.java
new file mode 100644
index 0000000..75bde2f
--- /dev/null
+++ b/core/src/main/java/dev/felnull/itts/core/util/PatternValidator.java
@@ -0,0 +1,94 @@
+package dev.felnull.itts.core.util;
+
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Optional;
+import java.util.regex.Pattern;
+import java.util.regex.PatternSyntaxException;
+
+/**
+ * 正規表現バリデーションユーティリティ
+ */
+public final class PatternValidator {
+
+    /**
+     * ReDoS脆弱性を持つ可能性のあるパターン
+     * ネストされた量子 (例: (a+)+, (a*)*) を検出
+     */
+    private static final Pattern REDOS_PATTERN = Pattern.compile(
+            "\\([^)]*[+*][^)]*\\)[+*]|\\([^)]*\\|[^)]*\\)[+*]"
+    );
+
+    private PatternValidator() {
+    }
+
+    /**
+     * 正規表現の構文を検証する
+     *
+     * @param regex 検証する正規表現
+     * @return 検証結果
+     */
+    @NotNull
+    public static ValidationResult validate(@NotNull String regex) {
+        try {
+            Pattern pattern = Pattern.compile(regex);
+
+            if (isPotentiallyDangerous(regex)) {
+                return ValidationResult.failure("この正規表現はパフォーマンス上の問題を引き起こす可能性があります");
+            }
+
+            return ValidationResult.success(pattern);
+        } catch (PatternSyntaxException e) {
+            return ValidationResult.failure("無効な正規表現です: " + e.getDescription());
+        }
+    }
+
+    /**
+     * 正規表現がReDoS脆弱性を持つ可能性があるかチェックする
+     *
+     * @param regex チェックする正規表現
+     * @return 危険な可能性がある場合はtrue
+     */
+    public static boolean isPotentiallyDangerous(@NotNull String regex) {
+        return REDOS_PATTERN.matcher(regex).find();
+    }
+
+    /**
+     * 正規表現バリデーションの結果
+     *
+     * @param valid   有効かどうか
+     * @param pattern コンパイル済みPattern (有効な場合のみ)
+     * @param error   エラーメッセージ (無効な場合のみ)
+     */
+    public record ValidationResult(boolean valid, Pattern pattern, String error) {
+
+        /**
+         * 成功結果を作成
+         *
+         * @param pattern コンパイル済みPattern
+         * @return 成功結果
+         */
+        public static ValidationResult success(@NotNull Pattern pattern) {
+            return new ValidationResult(true, pattern, null);
+        }
+
+        /**
+         * 失敗結果を作成
+         *
+         * @param error エラーメッセージ
+         * @return 失敗結果
+         */
+        public static ValidationResult failure(@NotNull String error) {
+            return new ValidationResult(false, null, error);
+        }
+
+        /**
+         * Patternを取得 (成功時のみ)
+         *
+         * @return コンパイル済みPattern
+         */
+        public Optional<Pattern> getPattern() {
+            return Optional.ofNullable(pattern);
+        }
+    }
+}
diff --git a/core/src/main/java/dev/felnull/itts/core/voice/VoiceManager.java b/core/src/main/java/dev/felnull/itts/core/voice/VoiceManager.java
index aa53393..a35359e 100644
--- a/core/src/main/java/dev/felnull/itts/core/voice/VoiceManager.java
+++ b/core/src/main/java/dev/felnull/itts/core/voice/VoiceManager.java
@@ -63,8 +63,8 @@ private void registerVoiceTypes(Supplier<List<VoiceType>> availableVoiceTypes) {
         return CompletableFuture.allOf(
                         voicevoxManager.init(),
                         coeiroinkManager.init(),
-                        sharevoxManager.init()).
-                thenAcceptAsync(v -> {
+                        sharevoxManager.init())
+                .thenAcceptAsync(v -> {
                     registerVoiceTypes(voiceTextManager::getVoiceTypes);
                     registerVoiceTypes(voicevoxManager::getAvailableVoiceTypes);
                     registerVoiceTypes(coeiroinkManager::getAvailableVoiceTypes);
diff --git a/core/src/main/java/dev/felnull/itts/core/voice/coeiroink/CoeiroinkManager.java b/core/src/main/java/dev/felnull/itts/core/voice/coeiroink/CoeiroinkManager.java
index a9c5aae..a1e233d 100644
--- a/core/src/main/java/dev/felnull/itts/core/voice/coeiroink/CoeiroinkManager.java
+++ b/core/src/main/java/dev/felnull/itts/core/voice/coeiroink/CoeiroinkManager.java
@@ -76,6 +76,9 @@ protected VoicevoxConfig getConfig() {
      * @return 初期化の非同期CompletableFuture
      */
     public CompletableFuture<?> init() {
+        if (!getConfig().isEnable()) {
+            return CompletableFuture.completedFuture(null);
+        }
         return balancer.init();
     }
 
@@ -115,12 +118,22 @@ protected List<CoeiroinkSpeaker> requestSpeakers(CIURL ciurl) throws IOException
                 .timeout(Duration.of(3000, ChronoUnit.MILLIS))
                 .build();
         HttpResponse<InputStream> rep = hc.send(req, HttpResponse.BodyHandlers.ofInputStream());
+
+        int statusCode = rep.statusCode();
+        if (statusCode != 200) {
+            throw new IOException(name + " API error: HTTP " + statusCode);
+        }
+
         JsonArray ja;
 
         try (InputStream stream = new BufferedInputStream(rep.body()); Reader reader = new InputStreamReader(stream, StandardCharsets.UTF_8)) {
             ja = GSON.fromJson(reader, JsonArray.class);
         }
 
+        if (ja == null) {
+            throw new IOException(name + " API returned invalid JSON response");
+        }
+
         ImmutableList.Builder<CoeiroinkSpeaker> speakerBuilder = new ImmutableList.Builder<>();
 
         for (JsonElement je : ja) {
diff --git a/core/src/main/java/dev/felnull/itts/core/voice/voicevox/VoicevoxManager.java b/core/src/main/java/dev/felnull/itts/core/voice/voicevox/VoicevoxManager.java
index 1fc846b..b607cd7 100644
--- a/core/src/main/java/dev/felnull/itts/core/voice/voicevox/VoicevoxManager.java
+++ b/core/src/main/java/dev/felnull/itts/core/voice/voicevox/VoicevoxManager.java
@@ -77,6 +77,9 @@ protected VoicevoxConfig getConfig() {
      * @return 初期化の非同期CompletableFuture
      */
     public CompletableFuture<?> init() {
+        if (!getConfig().isEnable()) {
+            return CompletableFuture.completedFuture(null);
+        }
         return balancer.init();
     }
 
@@ -116,12 +119,22 @@ protected List<VoicevoxSpeaker> requestSpeakers(VVURL vvurl) throws IOException,
                 .timeout(Duration.of(3000, ChronoUnit.MILLIS))
                 .build();
         HttpResponse<InputStream> rep = hc.send(req, HttpResponse.BodyHandlers.ofInputStream());
+
+        int statusCode = rep.statusCode();
+        if (statusCode != 200) {
+            throw new IOException(name + " API error: HTTP " + statusCode);
+        }
+
         JsonArray ja;
 
         try (InputStream stream = new BufferedInputStream(rep.body()); Reader reader = new InputStreamReader(stream, StandardCharsets.UTF_8)) {
             ja = GSON.fromJson(reader, JsonArray.class);
         }
 
+        if (ja == null) {
+            throw new IOException(name + " API returned invalid JSON response");
+        }
+
         ImmutableList.Builder<VoicevoxSpeaker> speakerBuilder = new ImmutableList.Builder<>();
 
         for (JsonElement je : ja) {
@@ -142,9 +155,21 @@ private JsonObject getQuery(String text, int speakerId) {
                     .build();
             HttpResponse<InputStream> rep = hc.send(req, HttpResponse.BodyHandlers.ofInputStream());
 
+            int statusCode = rep.statusCode();
+            if (statusCode != 200) {
+                throw new IOException(name + " audio_query API error: HTTP " + statusCode);
+            }
+
+            JsonObject result;
             try (InputStream stream = new BufferedInputStream(rep.body()); Reader reader = new InputStreamReader(stream, StandardCharsets.UTF_8)) {
-                return GSON.fromJson(reader, JsonObject.class);
+                result = GSON.fromJson(reader, JsonObject.class);
             }
+
+            if (result == null) {
+                throw new IOException(name + " audio_query API returned invalid JSON response");
+            }
+
+            return result;
         } catch (Exception e) {
             throw new RuntimeException(e);
         }
diff --git a/core/src/test/java/dev/felnull/itts/core/dict/DictionaryManagerTest.java b/core/src/test/java/dev/felnull/itts/core/dict/DictionaryManagerTest.java
new file mode 100644
index 0000000..497bc2e
--- /dev/null
+++ b/core/src/test/java/dev/felnull/itts/core/dict/DictionaryManagerTest.java
@@ -0,0 +1,104 @@
+package dev.felnull.itts.core.dict;
+
+import com.google.gson.JsonObject;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+/**
+ * DictionaryManagerのバリデーションテスト
+ */
+public class DictionaryManagerTest {
+
+    private final DictionaryManager dictionaryManager = new DictionaryManager();
+
+    @Nested
+    @DisplayName("serverDictLoadFromJson()のバリデーションテスト")
+    class ServerDictLoadFromJsonTests {
+
+        @Test
+        @DisplayName("バージョンが異なる場合は例外をスロー")
+        void invalidVersionThrowsException() {
+            JsonObject jo = new JsonObject();
+            jo.addProperty("version", 999);
+            JsonObject entry = new JsonObject();
+            entry.addProperty("test", "テスト");
+            jo.add("entry", entry);
+
+            RuntimeException exception = Assertions.assertThrows(RuntimeException.class, () ->
+                    dictionaryManager.serverDictLoadFromJson(jo, 123456L, false));
+            Assertions.assertEquals("Unsupported dictionary file version", exception.getMessage());
+        }
+
+        @Test
+        @DisplayName("versionフィールドがない場合は例外をスロー")
+        void missingVersionThrowsException() {
+            JsonObject jo = new JsonObject();
+            JsonObject entry = new JsonObject();
+            entry.addProperty("test", "テスト");
+            jo.add("entry", entry);
+
+            RuntimeException exception = Assertions.assertThrows(RuntimeException.class, () ->
+                    dictionaryManager.serverDictLoadFromJson(jo, 123456L, false));
+            Assertions.assertEquals("Unsupported dictionary file version", exception.getMessage());
+        }
+
+        @Test
+        @DisplayName("entryフィールドがない場合は例外をスロー")
+        void missingEntryFieldThrowsException() {
+            JsonObject jo = new JsonObject();
+            jo.addProperty("version", 0);
+
+            RuntimeException exception = Assertions.assertThrows(RuntimeException.class, () ->
+                    dictionaryManager.serverDictLoadFromJson(jo, 123456L, false));
+            Assertions.assertEquals("Invalid dictionary file format", exception.getMessage());
+        }
+
+        @Test
+        @DisplayName("entryがオブジェクトでない場合は例外をスロー")
+        void entryNotObjectThrowsException() {
+            JsonObject jo = new JsonObject();
+            jo.addProperty("version", 0);
+            jo.addProperty("entry", "not an object");
+
+            RuntimeException exception = Assertions.assertThrows(RuntimeException.class, () ->
+                    dictionaryManager.serverDictLoadFromJson(jo, 123456L, false));
+            Assertions.assertEquals("Invalid dictionary file format", exception.getMessage());
+        }
+
+        @Test
+        @DisplayName("エントリ数が上限を超える場合は例外をスロー")
+        void tooManyEntriesThrowsException() {
+            JsonObject jo = new JsonObject();
+            jo.addProperty("version", 0);
+            JsonObject entry = new JsonObject();
+
+            for (int i = 0; i <= 1000; i++) {
+                entry.addProperty("word" + i, "読み" + i);
+            }
+            jo.add("entry", entry);
+
+            RuntimeException exception = Assertions.assertThrows(RuntimeException.class, () ->
+                    dictionaryManager.serverDictLoadFromJson(jo, 123456L, false));
+            Assertions.assertTrue(exception.getMessage().contains("Dictionary entry count exceeds limit"));
+        }
+
+        @ParameterizedTest
+        @DisplayName("負のバージョン番号でも例外をスロー")
+        @ValueSource(ints = {-1, -100, Integer.MIN_VALUE})
+        void negativeVersionThrowsException(int version) {
+            JsonObject jo = new JsonObject();
+            jo.addProperty("version", version);
+            JsonObject entry = new JsonObject();
+            entry.addProperty("test", "テスト");
+            jo.add("entry", entry);
+
+            RuntimeException exception = Assertions.assertThrows(RuntimeException.class, () ->
+                    dictionaryManager.serverDictLoadFromJson(jo, 123456L, false));
+            Assertions.assertEquals("Unsupported dictionary file version", exception.getMessage());
+        }
+    }
+}
diff --git a/core/src/test/java/dev/felnull/itts/core/util/PatternValidatorTest.java b/core/src/test/java/dev/felnull/itts/core/util/PatternValidatorTest.java
new file mode 100644
index 0000000..984e3f9
--- /dev/null
+++ b/core/src/test/java/dev/felnull/itts/core/util/PatternValidatorTest.java
@@ -0,0 +1,157 @@
+package dev.felnull.itts.core.util;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+import org.junit.jupiter.params.provider.ValueSource;
+
+import java.util.stream.Stream;
+
+/**
+ * PatternValidatorのテストクラス
+ */
+public class PatternValidatorTest {
+
+    @Nested
+    @DisplayName("validate()メソッドのテスト")
+    class ValidateTests {
+
+        @ParameterizedTest
+        @DisplayName("有効な正規表現が成功を返す")
+        @ValueSource(strings = {
+                "^[a-z]+$",
+                "[0-9]{3}-[0-9]{4}",
+                "hello",
+                "\\d+",
+                "a*b+c?",
+                "^(foo|bar)$",
+                "[A-Za-z0-9_]+",
+                "\\w+@\\w+\\.\\w+",
+                "(?:abc)+",
+                "\\p{L}+"
+        })
+        void validPatternsReturnSuccess(String regex) {
+            PatternValidator.ValidationResult result = PatternValidator.validate(regex);
+            Assertions.assertTrue(result.valid());
+            Assertions.assertNotNull(result.pattern());
+            Assertions.assertNull(result.error());
+            Assertions.assertTrue(result.getPattern().isPresent());
+        }
+
+        @ParameterizedTest
+        @DisplayName("無効な構文がエラーを返す")
+        @MethodSource("invalidPatterns")
+        void invalidSyntaxReturnsError(String regex, String expectedErrorContains) {
+            PatternValidator.ValidationResult result = PatternValidator.validate(regex);
+            Assertions.assertFalse(result.valid());
+            Assertions.assertNull(result.pattern());
+            Assertions.assertNotNull(result.error());
+            Assertions.assertTrue(result.error().contains("無効な正規表現です"));
+            Assertions.assertTrue(result.getPattern().isEmpty());
+        }
+
+        private static Stream<Arguments> invalidPatterns() {
+            return Stream.of(
+                    Arguments.of("[a-z", "Unclosed character class"),
+                    Arguments.of("(abc", "Unclosed group"),
+                    Arguments.of("(?P<name>", "Unknown inline modifier"),
+                    Arguments.of("*abc", "Dangling meta character"),
+                    Arguments.of("+abc", "Dangling meta character"),
+                    Arguments.of("?abc", "Dangling meta character"),
+                    Arguments.of("\\", "Unexpected internal error"),
+                    Arguments.of("[z-a]", "Illegal character range")
+            );
+        }
+
+        @ParameterizedTest
+        @DisplayName("ReDoS脆弱性パターンがエラーを返す")
+        @ValueSource(strings = {
+                "(a+)+",
+                "(a*)*",
+                "(a+)*",
+                "(a*)+",
+                "(x+)+b",
+                "(a|b)+",
+                "(a|b)*",
+                "(x|y)+z"
+        })
+        void redosPatternsReturnError(String regex) {
+            PatternValidator.ValidationResult result = PatternValidator.validate(regex);
+            Assertions.assertFalse(result.valid());
+            Assertions.assertNull(result.pattern());
+            Assertions.assertNotNull(result.error());
+            Assertions.assertTrue(result.error().contains("パフォーマンス上の問題"));
+        }
+    }
+
+    @Nested
+    @DisplayName("isPotentiallyDangerous()メソッドのテスト")
+    class IsPotentiallyDangerousTests {
+
+        @ParameterizedTest
+        @DisplayName("危険なパターンを検出する")
+        @ValueSource(strings = {
+                "(a+)+",
+                "(a*)*",
+                "(a+)*",
+                "(a*)+",
+                "(x+)+b",
+                "(a|b)+",
+                "(a|b)*",
+                "(foo|bar)*"
+        })
+        void detectsDangerousPatterns(String regex) {
+            Assertions.assertTrue(PatternValidator.isPotentiallyDangerous(regex));
+        }
+
+        @ParameterizedTest
+        @DisplayName("安全なパターンは検出しない")
+        @ValueSource(strings = {
+                "^[a-z]+$",
+                "[0-9]{3}-[0-9]{4}",
+                "hello",
+                "\\d+",
+                "a+b+c+",
+                "^(foo|bar)$",
+                "[A-Za-z0-9_]+",
+                "\\w+@\\w+\\.\\w+",
+                "(?:abc)",
+                "a{1,10}"
+        })
+        void safePatternNotDetected(String regex) {
+            Assertions.assertFalse(PatternValidator.isPotentiallyDangerous(regex));
+        }
+    }
+
+    @Nested
+    @DisplayName("ValidationResultのテスト")
+    class ValidationResultTests {
+
+        @ParameterizedTest
+        @DisplayName("成功結果が正しく作成される")
+        @ValueSource(strings = {"abc", "\\d+", "[a-z]+"})
+        void successResultCreatedCorrectly(String regex) {
+            PatternValidator.ValidationResult result = PatternValidator.ValidationResult.success(
+                    java.util.regex.Pattern.compile(regex)
+            );
+            Assertions.assertTrue(result.valid());
+            Assertions.assertNotNull(result.pattern());
+            Assertions.assertNull(result.error());
+            Assertions.assertEquals(regex, result.pattern().pattern());
+        }
+
+        @ParameterizedTest
+        @DisplayName("失敗結果が正しく作成される")
+        @ValueSource(strings = {"エラー1", "エラー2", "無効な正規表現です"})
+        void failureResultCreatedCorrectly(String errorMessage) {
+            PatternValidator.ValidationResult result = PatternValidator.ValidationResult.failure(errorMessage);
+            Assertions.assertFalse(result.valid());
+            Assertions.assertNull(result.pattern());
+            Assertions.assertEquals(errorMessage, result.error());
+            Assertions.assertTrue(result.getPattern().isEmpty());
+        }
+    }
+}