diff --git a/.claude-plugin/plugin.json b/.claude-plugin/plugin.json
index 5352321..f860340 100644
--- a/.claude-plugin/plugin.json
+++ b/.claude-plugin/plugin.json
@@ -1,6 +1,6 @@
 {
   "name": "jsc-pkg",
-  "version": "0.0.1",
+  "version": "0.0.2",
   "description": "套件批次更新（nodejs/python/dotnet），失敗還原",
   "skills": "./skills",
   "author": {
diff --git a/.codex-plugin/plugin.json b/.codex-plugin/plugin.json
index 7df50c9..96a1b43 100644
--- a/.codex-plugin/plugin.json
+++ b/.codex-plugin/plugin.json
@@ -1,6 +1,6 @@
 {
   "name": "jsc-pkg",
-  "version": "0.0.1",
+  "version": "0.0.2",
   "description": "套件批次更新（nodejs/python/dotnet），失敗還原",
   "skills": "./skills"
 }
diff --git a/README.md b/README.md
index 8336161..6d92674 100644
--- a/README.md
+++ b/README.md
@@ -22,6 +22,7 @@ Marketplace 統一為 `jsc`（https://gitea.jsc.idv.tw/plugins/jsc.git），安
 | --- | --- |
 | `tools/list-packages.sh` | 偵測專案類型並列出所有外部套件與目前版本（TSV：ecosystem / name / current） |
 | `tools/latest-version.sh` | `latest-version.sh <ecosystem> <name>` 查最新穩定版（npm / pypi / nuget），查無 exit 4 |
+| `tools/apply-version.sh` | `apply-version.sh <ecosystem> <project dir> <name> <version>` 改寫版本來源檔案，把套件釘選到指定版本 |
 
 ## Skills 目錄
 
diff --git a/plugin.json b/plugin.json
index 0bb0358..31cbb33 100644
--- a/plugin.json
+++ b/plugin.json
@@ -1,6 +1,6 @@
 {
   "name": "jsc-pkg",
-  "version": "0.0.1",
+  "version": "0.0.2",
   "description": "套件批次更新（nodejs/python/dotnet），失敗還原",
   "skills": "./skills/"
 }
diff --git a/skills/pkg-update/SKILL.md b/skills/pkg-update/SKILL.md
index 03a5a3a..839d2a5 100644
--- a/skills/pkg-update/SKILL.md
+++ b/skills/pkg-update/SKILL.md
@@ -11,7 +11,7 @@ description: Update every external package of a project to its latest stable ver
 2. Confirm the working tree is clean: stop and report when uncommitted changes exist, so the revert cannot destroy them.
 3. Update ecosystem by ecosystem. This step **MUST run as a sub agent** (one sub agent per ecosystem):
    1. For every package, run `tools/latest-version.sh {ecosystem} {name}` to get the latest stable version.
-   2. Rewrite the version source file (package.json / requirements.txt / pyproject.toml / *.csproj).
+   2. Run `tools/apply-version.sh {ecosystem} {project dir} {name} {version}` to rewrite the version source file (package.json / requirements.txt / pyproject.toml / *.csproj).
    3. Re-resolve and install (`npm install` / `pip install -r` / `dotnet restore`).
 4. Run build and tests:
    - nodejs: `npm run build` (if present) plus `npm test` (if present).
diff --git a/tools/apply-version.sh b/tools/apply-version.sh
new file mode 100755
index 0000000..c519d8c
--- /dev/null
+++ b/tools/apply-version.sh
@@ -0,0 +1,130 @@
+#!/usr/bin/env sh
+# apply-version.sh — 改寫版本來源檔案，把套件釘選到指定版本。
+# 用法: apply-version.sh <ecosystem> <project-dir> <name> <version>
+#   ecosystem: nodejs | python | dotnet
+# 對應檔案（與 list-packages.sh 相同的解析邏輯）:
+#   nodejs → package.json（dependencies / devDependencies）
+#   python → requirements.txt（優先）或 pyproject.toml 的 [project] dependencies
+#   dotnet → *.csproj 的 PackageReference
+# 找不到對應檔案 exit 3；檔案中找不到該套件 exit 4
+set -u
+eco="${1:?ecosystem required (nodejs|python|dotnet)}"
+DIR="${2:?project dir required}"
+name="${3:?package name required}"
+version="${4:?version required}"
+
+case "$eco" in
+  nodejs)
+    [ -f "$DIR/package.json" ] || { echo "package.json not found in $DIR" >&2; exit 3; }
+    python3 - "$DIR/package.json" "$name" "$version" <<'EOF'
+import json,sys
+path,name,version=sys.argv[1],sys.argv[2],sys.argv[3]
+d=json.load(open(path,encoding="utf-8"))
+found=False
+for k in ("dependencies","devDependencies"):
+    if name in (d.get(k) or {}):
+        d[k][name]=version
+        found=True
+if not found:
+    sys.exit(4)
+with open(path,"w",encoding="utf-8") as f:
+    json.dump(d,f,indent=2,ensure_ascii=False)
+    f.write("\n")
+EOF
+    rc=$?
+    [ "$rc" -eq 0 ] || { echo "$name not found in $DIR/package.json" >&2; exit "$rc"; }
+    ;;
+
+  python)
+    if [ -f "$DIR/requirements.txt" ]; then
+      python3 - "$DIR/requirements.txt" "$name" "$version" <<'EOF'
+import re,sys
+path,name,version=sys.argv[1],sys.argv[2],sys.argv[3]
+pat=re.compile(r"([A-Za-z0-9_.\-\[\]]+)\s*(?:(?:==|>=|<=|~=|!=|>|<)\s*([^,;\s]+))?")
+lname=name.split("[")[0].lower()
+lines=open(path,encoding="utf-8").readlines()
+out=[]
+found=False
+for line in lines:
+    body=line.split("#")[0].strip()
+    m=pat.match(body)
+    if m and m.group(1).split("[")[0].lower()==lname:
+        out.append(f"{m.group(1)}=={version}\n")
+        found=True
+    else:
+        out.append(line)
+if not found:
+    sys.exit(4)
+open(path,"w",encoding="utf-8").writelines(out)
+EOF
+      rc=$?
+      [ "$rc" -eq 0 ] || { echo "$name not found in $DIR/requirements.txt" >&2; exit "$rc"; }
+    elif [ -f "$DIR/pyproject.toml" ]; then
+      python3 - "$DIR/pyproject.toml" "$name" "$version" <<'EOF'
+import re,sys
+path,name,version=sys.argv[1],sys.argv[2],sys.argv[3]
+pat=re.compile(r"([A-Za-z0-9_.\-\[\]]+)\s*(?:(?:==|>=|<=|~=|!=|>|<)\s*([^,;\s\"']+))?")
+lname=name.split("[")[0].lower()
+lines=open(path,encoding="utf-8").readlines()
+out=[]
+found=False
+for line in lines:
+    m=re.search(r'"([^"]+)"', line)
+    if m:
+        dep=m.group(1)
+        dm=pat.match(dep)
+        if dm and dm.group(1).split("[")[0].lower()==lname:
+            newdep=f"{dm.group(1)}=={version}"
+            line=line.replace(dep,newdep,1)
+            found=True
+    out.append(line)
+if not found:
+    sys.exit(4)
+open(path,"w",encoding="utf-8").writelines(out)
+EOF
+      rc=$?
+      [ "$rc" -eq 0 ] || { echo "$name not found in $DIR/pyproject.toml" >&2; exit "$rc"; }
+    else
+      echo "requirements.txt or pyproject.toml not found in $DIR" >&2
+      exit 3
+    fi
+    ;;
+
+  dotnet)
+    projs=$(find "$DIR" -maxdepth 3 -name '*.csproj' 2>/dev/null)
+    [ -n "$projs" ] || { echo "*.csproj not found in $DIR" >&2; exit 3; }
+    found=0
+    for proj in $projs; do
+      python3 - "$proj" "$name" "$version" <<'EOF'
+import re,sys
+path,name,version=sys.argv[1],sys.argv[2],sys.argv[3]
+text=open(path,encoding="utf-8").read()
+hit=[False]
+def repl(m):
+    tag=m.group(0)
+    inc=re.search(r'Include="([^"]+)"',tag)
+    if inc and inc.group(1)==name:
+        hit[0]=True
+        if re.search(r'Version="[^"]*"',tag):
+            tag=re.sub(r'Version="[^"]*"', 'Version="%s"'%version, tag)
+        elif tag.endswith("/>"):
+            tag=tag[:-2]+' Version="%s" />'%version
+        else:
+            tag=tag[:-1]+' Version="%s">'%version
+    return tag
+new_text=re.sub(r"<PackageReference\b[^>]*>", repl, text)
+if not hit[0]:
+    sys.exit(4)
+open(path,"w",encoding="utf-8").write(new_text)
+EOF
+      if [ $? -eq 0 ]; then
+        found=1
+        break
+      fi
+    done
+    [ "$found" -eq 1 ] || { echo "PackageReference $name not found under $DIR" >&2; exit 4; }
+    ;;
+
+  *) echo "unknown ecosystem: $eco" >&2; exit 2 ;;
+esac
+exit 0