diff --git a/CMakeLists.txt b/CMakeLists.txt
index 80390cc..93ac43a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,7 +1,7 @@
 cmake_minimum_required(VERSION 3.20)
 # macOS: the oldest release the library loads on. Without it the build machine's SDK version is used.
 set(CMAKE_OSX_DEPLOYMENT_TARGET "12.0" CACHE STRING "Minimum macOS version")
-project(ModAVDExtras VERSION 0.1.2 LANGUAGES C)
+project(ModAVDExtras VERSION 0.1.3 LANGUAGES C)
 
 set(CMAKE_C_STANDARD 11)
 set(CMAKE_C_STANDARD_REQUIRED ON)
diff --git a/release/0.1.3.SHA256SUMS.txt b/release/0.1.3.SHA256SUMS.txt
new file mode 100644
index 0000000..797460a
--- /dev/null
+++ b/release/0.1.3.SHA256SUMS.txt
@@ -0,0 +1,4 @@
+0fecc13ef0064ac8cf4e65934b75c32a555d6e7d50490ed84947b1eff7221acc  external_renderer_ipc.dll
+df53353f70adfe48853626fda103eb82197fa94d3caaf019f861787204467e53  libmodavd_extras.dylib
+df76579f3b6f583eed78650d28ea11aea69fadbf934dcfc79c73c84e5321c8e8  libmodavd_extras.so
+5ea1f80b23537886b05503e441691956d34381c93efe7b664777bd85bd653cdb  modavd_extras.dll
diff --git a/release/0.1.3.md b/release/0.1.3.md
new file mode 100644
index 0000000..19beee6
--- /dev/null
+++ b/release/0.1.3.md
@@ -0,0 +1,40 @@
+# ModAVDExtras v0.1.3
+
+- `modavd_extras.dll`：`5ea1f80b23537886b05503e441691956d34381c93efe7b664777bd85bd653cdb`
+- `external_renderer_ipc.dll`：`0fecc13ef0064ac8cf4e65934b75c32a555d6e7d50490ed84947b1eff7221acc`
+- `libmodavd_extras.dylib`：`df53353f70adfe48853626fda103eb82197fa94d3caaf019f861787204467e53`
+- `libmodavd_extras.so`：`df76579f3b6f583eed78650d28ea11aea69fadbf934dcfc79c73c84e5321c8e8`
+
+这一版只改 MuMu 外壳 `external_renderer_ipc.dll`：在 MAA 里填的实例编号直接就是 ModAVD 的编号，根目录改过端口段也不用自己算端口。截图库本身行为不变，接口版本还是 1。
+
+## 变更
+
+- `external_renderer_ipc.dll`：收到小于 5554 的 `index` 时当成 ModAVD 的实例编号，控制台端口按外壳所在根目录 `mas-avd.json` 的 `portBase` 算（`portBase + 10×编号`）（#12）。
+  - ModAVD 包会把外壳放在 `<根目录>\mumu-shim\shell\sdk\`；MAA 的 MuMu 路径填 `<根目录>\mumu-shim`，外壳从 MuMu 路径的上一级读 `mas-avd.json`。
+  - `portBase` 读不到、或者不是 1100–65400 之间 100 的整数倍，照旧按 20000 算。
+  - 控制台端口（≥ 5554）照旧原样认。
+- `modavd_version_string()` 返回 `"0.1.3"`。
+
+## 许可证与源码
+
+- LGPL-3.0-or-later。正文是 tag 下的 [LICENSE](https://github.com/ModAVD/ModAVDExtras/blob/v0.1.3/LICENSE)（LGPL-3.0）和 [COPYING](https://github.com/ModAVD/ModAVDExtras/blob/v0.1.3/COPYING)（GPL-3.0）；转发这些库时请一起带上。
+- 源码：<https://github.com/ModAVD/ModAVDExtras/tree/v0.1.3>。
+
+## 下载与核对
+
+四个文件都由本仓库的 release workflow 在 GitHub 上编出，和 tag 下的 `release/0.1.3.SHA256SUMS.txt` 核对过才上传。编译环境和 v0.1.2 一样：
+
+- Windows：`windows-2025`，`cmake -A x64`，`--config Release`。两个 DLL 都静态链接 C 运行库，只依赖 `KERNEL32`、`WS2_32`，编译带 `/Brepro`。
+- macOS：`macos-15`（Apple Silicon），`cmake -DCMAKE_BUILD_TYPE=Release`。
+- Linux：`ubuntu-24.04`（x64），`cmake -DCMAKE_BUILD_TYPE=Release`。
+
+请用附件 `SHA256SUMS.txt` 核对：Windows 上 `Get-FileHash .\modavd_extras.dll -Algorithm SHA256`，macOS 上 `shasum -a 256 libmodavd_extras.dylib`，Linux 上 `sha256sum libmodavd_extras.so`。
+
+## English
+
+This release only changes the MuMu shim `external_renderer_ipc.dll`: the instance index entered in MAA is the ModAVD instance index, and a root with its own port range needs no port arithmetic. The capture library itself is unchanged; the API version is still 1.
+
+- `external_renderer_ipc.dll`: an `index` below 5554 is taken as a ModAVD instance index, and the console port is `portBase + 10 × index`, with `portBase` read from `mas-avd.json` in the root the shim sits in (#12). The ModAVD package puts the shim in `<root>\mumu-shim\shell\sdk\`; MAA's MuMu path is `<root>\mumu-shim`, and the shim reads `mas-avd.json` one level above it. Without a valid `portBase` (a multiple of 100 between 1100 and 65400) it uses 20000 as before. Console ports (5554 and above) are still taken as they are.
+- `modavd_version_string()` returns `"0.1.3"`.
+- License: LGPL-3.0-or-later; the texts are [LICENSE](https://github.com/ModAVD/ModAVDExtras/blob/v0.1.3/LICENSE) (LGPL-3.0) and [COPYING](https://github.com/ModAVD/ModAVDExtras/blob/v0.1.3/COPYING) (GPL-3.0) at the tag. Ship them with the libraries. Source: <https://github.com/ModAVD/ModAVDExtras/tree/v0.1.3>.
+- All four files are built by this repository's release workflow on GitHub, the same way as v0.1.2, and checked against `release/0.1.3.SHA256SUMS.txt` at the tag before upload. Check them with the attached `SHA256SUMS.txt`.