diff --git a/.github/workflows/download_test.yml b/.github/workflows/download_test.yml
index 2aebff525..14970ded4 100644
--- a/.github/workflows/download_test.yml
+++ b/.github/workflows/download_test.yml
@@ -185,28 +185,24 @@ jobs:
       - uses: actions/checkout@v3
       - name: Set up Rust
         uses: ./.github/actions/rust-toolchain-from-file
-
       - name: Get prerelease latest version
         if: ${{ env.VERSION == 'prerelease-latest' }}
         run: |
           VERSION=$(
-            curl -s https://api.github.com/repos/VOICEVOX/voicevox_core/releases \
+            curl -sSf https://api.github.com/repos/VOICEVOX/voicevox_core/releases \
               -H 'authorization: Bearer ${{ github.token }}' \
               -H 'content-type: application/json' |
             jq -er '.[0].tag_name'
           )
           echo "VERSION=$VERSION" >> "$GITHUB_ENV"
-
       - name: Execute download command
         run: ${{ matrix.download_command }} --version ${{ env.VERSION }}
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-
       - name: Check downloaded version
         run: |
           [ -e "${{ matrix.download_dir }}/VERSION" ]
           [ "$(cat "${{ matrix.download_dir }}/VERSION")" = "${{ env.VERSION }}" ]
-
       - name: Check downloaded files
         run: |
           mapfile -t items < <(echo -n '${{ matrix.check_items }}')
diff --git a/.github/workflows/java_lint.yml b/.github/workflows/java_lint.yml
new file mode 100644
index 000000000..b631819b8
--- /dev/null
+++ b/.github/workflows/java_lint.yml
@@ -0,0 +1,31 @@
+name: "Lint Java code"
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    paths:
+      - ./crates/voicevox_core_java_api/**/*.java
+      - ./crates/voicevox_core_java_api/gradle/**
+      - ./crates/voicevox_core_java_api/gradlew
+      - ./crates/voicevox_core_java_api/settings.gradle
+      - ./.github/workflows/java_lint.yml
+
+defaults:
+  run:
+    shell: bash
+    working-directory: ./crates/voicevox_core_java_api
+
+jobs:
+  java-lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-java@v2
+        with:
+          java-version: "11"
+          distribution: "adopt"
+      - name: Check code style
+        run: |
+          ./gradlew spotlessCheck --info
diff --git a/.github/workflows/python_lint.yml b/.github/workflows/python_lint.yml
new file mode 100644
index 000000000..c12b256cf
--- /dev/null
+++ b/.github/workflows/python_lint.yml
@@ -0,0 +1,40 @@
+name: "Lint Python code"
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    paths:
+      - ./example/python/**/*.py
+      - ./crates/voicevox_core_python_api/**/*.py
+      - ./crates/voicevox_core_python_api/requirements*.txt
+      - ./crates/voicevox_core_python_api/pyproject.toml
+      - ./.github/workflows/python_lint.yml
+
+defaults:
+  run:
+    shell: bash
+    working-directory: ./crates/voicevox_core_python_api
+
+jobs:
+  python:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-python@v4
+        with:
+          python-version: "3.8"
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install -r requirements-dev.txt
+      - name: Check code style for voicevox_core_python_api
+        run: |
+          black --check .
+          isort --check .
+      - name: Check code style for example/python
+        working-directory: ./example/python
+        run: |
+          black --check .
+          isort --check .
diff --git a/crates/download/src/main.rs b/crates/download/src/main.rs
index fba1bc342..e52ca45f2 100644
--- a/crates/download/src/main.rs
+++ b/crates/download/src/main.rs
@@ -53,15 +53,15 @@ struct Args {
     min: bool,
 
     /// 出力先の指定
-    #[arg(short, long, default_value(DEFAULT_OUTPUT))]
+    #[arg(short, long, value_name("DIRECTORY"), default_value(DEFAULT_OUTPUT))]
     output: PathBuf,
 
     /// ダウンロードするvoicevox_coreのバージョンの指定
-    #[arg(short, long, default_value("latest"))]
+    #[arg(short, long, value_name("GIT_TAG_OR_LATEST"), default_value("latest"))]
     version: String,
 
     /// 追加でダウンロードするライブラリのバージョン
-    #[arg(long, default_value("latest"))]
+    #[arg(long, value_name("GIT_TAG_OR_LATEST"), default_value("latest"))]
     additional_libraries_version: String,
 
     /// ダウンロードするデバイスを指定する(cudaはlinuxのみ)
diff --git a/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/Synthesizer.java b/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/Synthesizer.java
index 5047048b8..98bf9f403 100644
--- a/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/Synthesizer.java
+++ b/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/Synthesizer.java
@@ -55,7 +55,6 @@ public boolean isLoadedVoiceModel(String voiceModelId) {
    * @param text テキスト。
    * @param styleId スタイルID。
    * @return {@link CreateAudioQueryConfigurator}。
-   *
    * @see CreateAudioQueryConfigurator#execute
    */
   @Nonnull
@@ -69,7 +68,6 @@ public CreateAudioQueryConfigurator createAudioQuery(String text, int styleId) {
    * @param text テキスト。
    * @param styleId スタイルID。
    * @return {@link CreateAccentPhrasesConfigurator}。
-   *
    * @see CreateAccentPhrasesConfigurator#execute
    */
   @Nonnull
@@ -137,7 +135,6 @@ public List<AccentPhrase> replaceMoraPitch(List<AccentPhrase> accentPhrases, int
    * @param audioQuery {@link AudioQuery}。
    * @param styleId スタイルID。
    * @return {@link SynthesisConfigurator}。
-   *
    * @see SynthesisConfigurator#execute
    */
   @Nonnull
@@ -151,7 +148,6 @@ public SynthesisConfigurator synthesis(AudioQuery audioQuery, int styleId) {
    * @param text テキスト。
    * @param styleId スタイルID。
    * @return {@link TtsConfigurator}。
-   *
    * @see TtsConfigurator#execute
    */
   @Nonnull
diff --git a/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/UserDict.java b/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/UserDict.java
index e31d56338..d75924feb 100644
--- a/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/UserDict.java
+++ b/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/UserDict.java
@@ -6,7 +6,6 @@
 import com.google.gson.internal.LinkedTreeMap;
 import jakarta.validation.constraints.Max;
 import jakarta.validation.constraints.Min;
-
 import java.lang.ref.Cleaner;
 import java.util.HashMap;
 import javax.annotation.Nonnull;
@@ -177,7 +176,7 @@ public static class Word {
     /**
      * UserDict.Wordを作成する。
      *
-     * @param surface       言葉の表層形。
+     * @param surface 言葉の表層形。
      * @param pronunciation 言葉の発音。
      * @throws IllegalArgumentException pronunciationが不正な場合。
      */
diff --git a/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/VoiceModel.java b/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/VoiceModel.java
index 6b157fdba..518f1de31 100644
--- a/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/VoiceModel.java
+++ b/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/VoiceModel.java
@@ -47,25 +47,25 @@ public static class SpeakerMeta {
     @SerializedName("name")
     @Expose
     @Nonnull
-    final String name;
+    public final String name;
 
     /** 話者に属するスタイル。 */
     @SerializedName("styles")
     @Expose
     @Nonnull
-    final StyleMeta[] styles;
+    public final StyleMeta[] styles;
 
     /** 話者のUUID。 */
     @SerializedName("speaker_uuid")
     @Expose
     @Nonnull
-    final String speakerUuid;
+    public final String speakerUuid;
 
     /** 話者のバージョン。 */
     @SerializedName("version")
     @Expose
     @Nonnull
-    final String version;
+    public final String version;
 
     private SpeakerMeta() {
       // GSONからコンストラクトするため、このメソッドは呼ばれることは無い。
@@ -83,12 +83,12 @@ public static class StyleMeta {
     @SerializedName("name")
     @Expose
     @Nonnull
-    final String name;
+    public final String name;
 
     /** スタイルID。 */
     @SerializedName("id")
     @Expose
-    final int id;
+    public final int id;
 
     private StyleMeta() {
       this.name = "";
diff --git a/crates/voicevox_core_python_api/python/test/test_user_dict_load.py b/crates/voicevox_core_python_api/python/test/test_user_dict_load.py
index 8c506a50f..d9829e6da 100644
--- a/crates/voicevox_core_python_api/python/test/test_user_dict_load.py
+++ b/crates/voicevox_core_python_api/python/test/test_user_dict_load.py
@@ -2,8 +2,9 @@
 # AudioQueryのkanaを比較して変化するかどうかで判断する。
 
 from uuid import UUID
-import pytest
+
 import conftest  # noqa: F401
+import pytest
 import voicevox_core  # noqa: F401
 
 
diff --git a/crates/voicevox_core_python_api/python/test/test_user_dict_manipulate.py b/crates/voicevox_core_python_api/python/test/test_user_dict_manipulate.py
index c9bc2c454..f7902ea94 100644
--- a/crates/voicevox_core_python_api/python/test/test_user_dict_manipulate.py
+++ b/crates/voicevox_core_python_api/python/test/test_user_dict_manipulate.py
@@ -2,8 +2,9 @@
 # どのコードがどの操作を行っているかはコメントを参照。
 
 import os
-from uuid import UUID
 import tempfile
+from uuid import UUID
+
 import pytest
 import voicevox_core  # noqa: F401
 
diff --git a/crates/voicevox_core_python_api/python/voicevox_core/__init__.py b/crates/voicevox_core_python_api/python/voicevox_core/__init__.py
index f59f705dd..ce6245bfc 100644
--- a/crates/voicevox_core_python_api/python/voicevox_core/__init__.py
+++ b/crates/voicevox_core_python_api/python/voicevox_core/__init__.py
@@ -11,15 +11,15 @@
     UserDictWord,
     UserDictWordType,
 )
-from ._rust import (
-    __version__,
+from ._rust import (  # noqa: F401
     OpenJtalk,
     Synthesizer,
+    UserDict,
     VoiceModel,
     VoicevoxError,
-    UserDict,
+    __version__,
     supported_devices,
-)  # noqa: F401
+)
 
 __all__ = [
     "__version__",
diff --git a/crates/voicevox_core_python_api/python/voicevox_core/_models.py b/crates/voicevox_core_python_api/python/voicevox_core/_models.py
index b559100be..c1cd9ccca 100644
--- a/crates/voicevox_core_python_api/python/voicevox_core/_models.py
+++ b/crates/voicevox_core_python_api/python/voicevox_core/_models.py
@@ -4,7 +4,7 @@
 
 import pydantic
 
-from ._rust import _validate_pronunciation, _to_zenkaku
+from ._rust import _to_zenkaku, _validate_pronunciation
 
 
 @pydantic.dataclasses.dataclass
diff --git a/crates/voicevox_core_python_api/python/voicevox_core/_rust.pyi b/crates/voicevox_core_python_api/python/voicevox_core/_rust.pyi
index e9c700a91..324ea0117 100644
--- a/crates/voicevox_core_python_api/python/voicevox_core/_rust.pyi
+++ b/crates/voicevox_core_python_api/python/voicevox_core/_rust.pyi
@@ -1,5 +1,5 @@
 from pathlib import Path
-from typing import Dict, Final, List, Literal, Union, TYPE_CHECKING
+from typing import TYPE_CHECKING, Dict, Final, List, Literal, Union
 from uuid import UUID
 
 import numpy as np
diff --git a/example/python/run.py b/example/python/run.py
index 04feef83e..026b67a80 100644
--- a/example/python/run.py
+++ b/example/python/run.py
@@ -7,13 +7,8 @@
 from typing import Tuple
 
 import voicevox_core
-from voicevox_core import (
-    AccelerationMode,
-    AudioQuery,
-    OpenJtalk,
-    Synthesizer,
-    VoiceModel,
-)
+from voicevox_core import (AccelerationMode, AudioQuery, OpenJtalk,
+                           Synthesizer, VoiceModel)
 
 
 async def main() -> None: