diff --git a/web-api/README.md b/web-api/README.md
new file mode 100644
index 00000000..d6cf5171
--- /dev/null
+++ b/web-api/README.md
@@ -0,0 +1,23 @@
+# web 服务
+
+实现 web 服务，提供 RESTful API 接口。
+
+```json
+{
+    "/infer": {
+        "session_id": "String",
+        "inputs": [{
+            "role": "String",
+            "content": "String"
+        }],
+        "dialog_pos": "int"
+    },
+    "/fork": {
+        "session_id": "String",
+        "new_session_id": "String"
+    },
+    "/drop": {
+        "session_id": "String"
+    }
+}
+```
diff --git a/web-api/src/lib.rs b/web-api/src/lib.rs
index b1e635a8..755d8bfc 100644
--- a/web-api/src/lib.rs
+++ b/web-api/src/lib.rs
@@ -1,3 +1,5 @@
+#![doc = include_str!("../README.md")]
+
 mod handlers;
 mod manager;
 mod response;