diff --git a/readme.md b/readme.md
index edc3df70..600e5f7f 100644
--- a/readme.md
+++ b/readme.md
@@ -14,11 +14,28 @@ realm is a simple, high performance relay server written in rust.
 - Low resources cost.
 
 ## Usage
-This executable takes 2 arguments:
-- -l [--local] local socket address. Default address 127.0.0.1 is used when the address is omitted.
-- -r [--remote] remote socker address. Both domain and ip address are accepted. If a domain is passed, the resolver will try to resolve and update the ip address regularly, ipv4 is preferred.
-
-An example to listen on port 30000 and forwarding traffic to example.com:12345 is as follows.
+```bash
+realm -c config.json
+```
+>example.json
+```json
+{
+	"dns_mode": "Ipv4Only",
+	"endpoints": [
+		{
+			"local": "0.0.0.0:5000",
+			"remote": "1.1.1.1:443",
+			"udp": false
+		}
+        {
+		    "local": "0.0.0.0:10000",
+		    "remote": "www.google.com:443",
+			"udp": true
+		}
+	]
+}
+```
+>dns_mode
 ```
-./realm -l 127.0.0.1:30000 -r example.com:12345
+Ipv4Only|Ipv6Only|Ipv4AndIpv6|Ipv4thenIpv6|Ipv6thenIpv4
 ```
diff --git a/src/cmd/mod.rs b/src/cmd/mod.rs
index b60e32b2..4079fda9 100644
--- a/src/cmd/mod.rs
+++ b/src/cmd/mod.rs
@@ -1,7 +1,11 @@
 use clap::{Arg, App, SubCommand};
 
+mod nav;
+pub use nav::run_navigator;
+
 pub enum CmdInput {
     Config(String),
+    Navigate,
     None,
 }
 
@@ -17,9 +21,18 @@ pub fn scan() -> CmdInput {
                 .help("specify a config file in json format")
                 .takes_value(true),
         )
+        .subcommand(
+            SubCommand::with_name("nav")
+                .about("An Interactive configuration editor")
+                .version("0.1.0")
+                .author("zephyr <i@zephyr.moe>"),
+        )
         .get_matches();
     if let Some(config) = matches.value_of("config") {
         return CmdInput::Config(config.to_string());
     }
+    if let Some(_) = matches.subcommand_matches("nav") {
+        return CmdInput::Navigate;
+    }
     CmdInput::None
 }
diff --git a/src/cmd/nav.rs b/src/cmd/nav.rs
new file mode 100644
index 00000000..297cac73
--- /dev/null
+++ b/src/cmd/nav.rs
@@ -0,0 +1,3 @@
+pub fn run_navigator() {
+    todo!()
+}
diff --git a/src/config/endpoint_config.rs b/src/config/endpoint_config.rs
index c91a8dca..13f3df30 100644
--- a/src/config/endpoint_config.rs
+++ b/src/config/endpoint_config.rs
@@ -1,5 +1,4 @@
 use serde::{Serialize, Deserialize};
-
 use crate::relay::Endpoint;
 
 #[derive(Debug, Serialize, Deserialize)]
diff --git a/src/config/mod.rs b/src/config/mod.rs
index 4a15f2e9..8e58f86e 100644
--- a/src/config/mod.rs
+++ b/src/config/mod.rs
@@ -4,7 +4,6 @@ use serde::{Serialize, Deserialize};
 
 mod dns_mode;
 mod endpoint_config;
-
 pub use dns_mode::DnsMode;
 pub use endpoint_config::EndpointConfig;
 
diff --git a/src/main.rs b/src/main.rs
index 6ccd9e04..9eaf28db 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -10,6 +10,7 @@ use relay::Endpoint;
 fn main() {
     match cmd::scan() {
         CmdInput::Config(c) => start_from_config(c),
+        CmdInput::Navigate => cmd::run_navigator(),
         CmdInput::None => {}
     }
 }
diff --git a/src/relay/mod.rs b/src/relay/mod.rs
index 940bc673..87bb0ed7 100644
--- a/src/relay/mod.rs
+++ b/src/relay/mod.rs
@@ -8,7 +8,6 @@ mod dns;
 mod tcp;
 mod udp;
 mod types;
-
 pub use types::{Endpoint, RemoteAddr};
 pub use dns::init_resolver;