diff --git a/api/README.md b/api/README.md
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+# mizu API server
+API server for MIZU
+Basic APIs:
+* /fetch - retrieve traffic data
+* /stats - retrieve statistics of collected data
+* /viewer - web ui
diff --git a/cli/README.md b/cli/README.md
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+# mizu CLI
+Usage examples
+
diff --git a/tap/README.md b/tap/README.md
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+# mizu TAP module
diff --git a/ui/README.md b/ui/README.md
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+# mizu UI
+web app traffic viewer