diff --git a/barg.js b/barg.js
index de31449..5ffa56c 100644
--- a/barg.js
+++ b/barg.js
@@ -58,7 +58,7 @@ function parse_input(spec, input) {
 
   let position = 0;
   let level = 1;
-  let commands = ["root"];
+  let commands = ["_"];
 
   function ref(...rest) {
     return commands.slice(0, level).concat(rest).join(".");
@@ -86,6 +86,7 @@ function parse_input(spec, input) {
           // Schema
           schema[ref(name, "type")] = "command";
           schema[ref(name, "help")] = help;
+          schema[ref(name, "args")] = "";
 
           // Alias
           for (const alias of aliases) {
@@ -110,17 +111,18 @@ function parse_input(spec, input) {
           const entry = { required: false, kind: "positional" };
           for (const element of elements) {
             const [attribute, attr_value] = element.split(":");
+            let default_value;
 
             if (attribute === "required") entry.required = true;
             else if (attribute === "repeatable") entry.repeatable = true;
             else if (attribute === "help") entry.help = attr_value;
-            else if (attribute === "default") entry.default_value = attr_value;
             else if (attribute === "dest") entry.dest = attr_value;
             else if (attribute === "type") entry.kind = attr_value;
+            else if (attribute === "default") default_value = attr_value;
 
             // Defaults
             if (entry.dest === undefined) entry.dest = name;
-            if (entry.value === undefined) entry.value = entry.default_value;
+            if (entry.value === undefined) entry.value = default_value;
           }
 
           // Alias
@@ -144,6 +146,10 @@ function parse_input(spec, input) {
           for (const [key, value] of Object.entries(entry)) {
             schema[ref(name, key)] = value;
           }
+
+          // Register arg to command
+          schema[ref("args")] += `${name},`;
+
           break;
         }
         default:
@@ -151,7 +157,7 @@ function parse_input(spec, input) {
       }
     }
 
-    commands = ["root"];
+    commands = ["_"];
     level = 1;
     position = 0;
   }
@@ -166,22 +172,28 @@ function parse_input(spec, input) {
   }
 
   generate_schema();
+  log({ schema, alias_map });
 
   while (tokens.length > 0) {
     const token = take_one(tokens);
     const [token_type, token_key] = token.split("::");
-    if (token_type === "rest") {
-      values["__rest"] = token_key;
-      continue;
-    }
 
     // Bubble up arguments -> Loop over all command levels starting by the latest
     let found = false;
     for (level = commands.length; level >= 1; level--) {
       let entry_ref = get_entry_ref(token);
 
-      // Positional arguments are valid only for the latest command
+      // Check for rest argument
+      if (token_type === "rest") {
+        entry_ref = get_entry_ref("__rest");
+      }
+
+      if (token_type === "narg") {
+        entry_ref = get_entry_ref(token);
+      }
+
       if (!entry_ref && level === commands.length && token_type === "unk") {
+        // Positional arguments are valid only for the latest command
         entry_ref = get_entry_ref(`pos::${position}`);
         if (entry_ref) {
           position += 1;
@@ -199,15 +211,16 @@ function parse_input(spec, input) {
       } else if (entry_type === "argument") {
         const kind = get_entry_item(entry_ref, "kind");
         const dest = get_entry_item(entry_ref, "dest");
-        const value = get_entry_item(entry_ref, "value");
+        const default_value = get_entry_item(entry_ref, "value");
 
-        values[dest] = value; // default one
-
-        if (kind === "flag") values[dest] = true;
-        else if (kind === "option") values[dest] = next_token_value();
-        else if (kind === "positional") values[dest] = token_key;
-        else if (kind === "rest") values[dest] = token_key;
+        let value;
+        if (kind === "flag") value = true;
+        else if (kind === "option") value = next_token_value();
+        else if (kind === "positional") value = token_key;
+        else if (kind === "rest") value = token_key;
         else throw new Error(`Invalid attribute type: '${kind}'`);
+
+        values[dest] = value;
       }
 
       found = true;
@@ -219,23 +232,26 @@ function parse_input(spec, input) {
     }
   }
 
+  commands.shift();
   log({ commands, values });
   return values;
 }
 
 const SPEC = [
   "command;build;Build a dev container",
-  "argument;from;type:option;map:from_name;help:Name of the base container",
+  "argument;from;type:option;dest:from_name;help:Name of the base container",
   "argument;name;type:positional;required;help:Name of the container",
-  "argument;image,i;type:option;required;map:image_name;help:Base image",
-  "argument;include,I;type:option;repeatable;map:include_paths;help:Include paths",
+  "argument;name;type:option;required;help:Name of the container",
+  "argument;image,i;type:option;required;dest:image_name;help:Base image",
+  "argument;include,I;type:option;repeatable;dest:include_paths;help:Include paths",
   "argument;verbose,v;type:flag;repeatable;default:0;help:Increase verbosity (-v, -vv, ...)",
   "argument;quiet,q;type:flag;default:false;help:Suppress all output",
-  "argument;cmd;type:rest;map:cmd_rest;help:Command and args to run inside the container",
+  "argument;cmd;type:rest;help:Command and args to run inside the container",
   "argument;name;dest:name_opt;type:option;help:Building container name",
   "command;container;Container building",
   "argument;dev;type:flag;help:Is dev or not",
   "argument;name;required;help:Building container name",
+  "argument;cmd;type:rest;dest:cmd_rest;help:Command and args to run inside the container",
   "end",
   "argument;external;required;help:Name of the external container",
   "end",
@@ -248,6 +264,7 @@ const SPEC = [
 const INPUTS = [
   "dev build --from base-dev --image node:18 --include src --include test -v -v -q mycontainer -- npm run start",
   "dev build container --dev --name webapp externalContainer",
+  "dev build container --dev --name webapp externalContainer -- echo hi",
   "dev stop mycontainer --kill",
   "dev build --from alpine --image node:20 mybox -- echo hi",
 ];