docs: add kcl-lang/cli repo introduction documents

Signed-off-by: peefy <xpf6677@163.com>

Author: Peefy

README.md

@@ -15,7 +15,13 @@
 
 ## Introduction
 
-`kcl` is a command-line interface that includes language core features, IDE features, package management tools, community integration, and other tools.
+`kcl` is a command-line interface that includes language core features, IDE features, package management tools, community integration, and other tools. It now integrates the following tools:
+
++ [Open API Tool](https://github.com/kcl-lang/kcl-openapi)
++ [Package Manage Tool](https://github.com/kcl-lang/kpm)
++ [KCL Playground](https://github.com/kcl-lang/kcl-playground)
+
+In the future, we will unify and integrate these dispersed tools into the `kcl-lang/tools` repo.
 
 ## Installation