diff --git a/README.md b/README.md
index e7d7e77..4763df2 100644
--- a/README.md
+++ b/README.md
@@ -100,6 +100,8 @@ Playbook：TSL（`.tsl`/`.tsf`）+ C++ + Python 工程规范与代理规则合
    sh docs/standards/playbook/scripts/sync_standards.sh tsl cpp
    ```
 
+   > 说明：若项目根目录没有 `AGENTS.md`，`sync_standards.*` 会自动生成最小版；已存在则不会覆盖。
+
 3. 验收（任意满足其一即可）：
 
    - 目录存在：`.agents/tsl/`
@@ -112,6 +114,25 @@ Playbook：TSL（`.tsl`/`.tsf`）+ C++ + Python 工程规范与代理规则合
    - `docs/standards/playbook/`（标准快照）
    - `.agents/tsl/`（落地规则集）
    - `.gitattributes`（managed block 更新）
+   - `AGENTS.md`（若本次自动生成）
+
+#### 新项目 / 旧项目（命令示例）
+
+新项目（无 `.agents/` 与 `AGENTS.md`）：
+
+```bash
+git subtree add --prefix docs/standards/playbook https://git.mytsl.cn/csh/playbook.git main --squash
+sh docs/standards/playbook/scripts/sync_standards.sh tsl
+```
+
+旧项目（已有 `AGENTS.md`）：
+
+```bash
+git subtree pull --prefix docs/standards/playbook https://git.mytsl.cn/csh/playbook.git main --squash
+sh docs/standards/playbook/scripts/sync_standards.sh tsl
+```
+
+旧项目的 `AGENTS.md` 不会被覆盖；如需指向 `.agents/`，请手动对齐内容。
 
 #### 可选：项目包装脚本（多 playbook 串联）
 
diff --git a/scripts/sync_standards.bat b/scripts/sync_standards.bat
index 59491d2..b4d0c6c 100644
--- a/scripts/sync_standards.bat
+++ b/scripts/sync_standards.bat
@@ -120,6 +120,16 @@ if not exist "%AGENTS_ROOT%\index.md" (
   echo Created .agents\index.md
 )
 
+if not exist "%ROOT%\AGENTS.md" (
+  > "%ROOT%\AGENTS.md" echo # Agent Instructions
+  >> "%ROOT%\AGENTS.md" echo.
+  >> "%ROOT%\AGENTS.md" echo 请以 `.agents/` 下的规则为准：
+  >> "%ROOT%\AGENTS.md" echo.
+  >> "%ROOT%\AGENTS.md" echo - 入口：`.agents/index.md`
+  >> "%ROOT%\AGENTS.md" echo - 语言规则：`.agents/tsl/index.md`、`.agents/cpp/index.md`、`.agents/python/index.md`
+  echo Created AGENTS.md
+)
+
 :SyncGitAttr
 if exist "%GITATTR_SRC%" (
   if /I "%SYNC_GITATTR_MODE%"=="skip" (
diff --git a/scripts/sync_standards.ps1 b/scripts/sync_standards.ps1
index 6868da5..716612b 100644
--- a/scripts/sync_standards.ps1
+++ b/scripts/sync_standards.ps1
@@ -121,6 +121,19 @@ if (-not (Test-Path $AgentsIndex)) {
   Write-Host "Created .agents/index.md"
 }
 
+$AgentsMd = Join-Path $Root "AGENTS.md"
+if (-not (Test-Path $AgentsMd)) {
+@'
+# Agent Instructions
+
+请以 `.agents/` 下的规则为准：
+
+- 入口：`.agents/index.md`
+- 语言规则：`.agents/tsl/index.md`、`.agents/cpp/index.md`、`.agents/python/index.md`
+'@ | Set-Content -Path $AgentsMd -Encoding UTF8
+  Write-Host "Created AGENTS.md"
+}
+
 $GitAttrDst = Join-Path $Root ".gitattributes"
 if (Test-Path $GitAttrSrc) {
   $mode = $env:SYNC_GITATTR_MODE
diff --git a/scripts/sync_standards.sh b/scripts/sync_standards.sh
index 9985545..0053404 100644
--- a/scripts/sync_standards.sh
+++ b/scripts/sync_standards.sh
@@ -125,6 +125,19 @@ EOF
   echo "Created .agents/index.md"
 fi
 
+AGENTS_MD="$ROOT/AGENTS.md"
+if [ ! -f "$AGENTS_MD" ]; then
+  cat >"$AGENTS_MD" <<'EOF'
+# Agent Instructions
+
+请以 `.agents/` 下的规则为准：
+
+- 入口：`.agents/index.md`
+- 语言规则：`.agents/tsl/index.md`、`.agents/cpp/index.md`、`.agents/python/index.md`
+EOF
+  echo "Created AGENTS.md"
+fi
+
 echo "Synced agents ruleset to $AGENTS_DST."
 
 GITATTR_DST="$ROOT/.gitattributes"