diff --git a/src/generator/json_registry.rs b/src/generator/json_registry.rs
index 52dd573..53adba3 100644
--- a/src/generator/json_registry.rs
+++ b/src/generator/json_registry.rs
@@ -1,5 +1,11 @@
+use crate::generator::utils::SourceContext;
+
 use protobuf::{
-    Message, UnknownValueRef, descriptor::DescriptorProto, descriptor::field_descriptor_proto::Type,
+    Message, UnknownValueRef,
+    descriptor::{
+        DescriptorProto, FileDescriptorProto,
+        field_descriptor_proto::{Label, Type},
+    },
 };
 use serde::{Deserialize, Serialize};
 use std::collections::HashMap;
@@ -52,12 +58,15 @@ impl From<Type> for WireType {
 
 /// Generate json registry from given messages
 pub fn generate_json_registry(
+    fd: &FileDescriptorProto,
     messages: &[DescriptorProto],
     package: &str,
     parent_path: Option<&str>,
     out: &mut ProtoJsonRegistry,
 ) {
-    for message in messages {
+    let ctx = SourceContext::new(fd);
+
+    for (i, message) in messages.iter().enumerate() {
         if message.options.map_entry() {
             continue;
         }
@@ -77,7 +86,7 @@ pub fn generate_json_registry(
 
         // iterate nested types
         if !message.nested_type.is_empty() {
-            generate_json_registry(&message.nested_type, package, Some(&scoped_name), out);
+            generate_json_registry(fd, &message.nested_type, package, Some(&scoped_name), out);
         }
 
         // collect xor constants
@@ -91,17 +100,43 @@ pub fn generate_json_registry(
                 None
             };
 
+            let is_repeated = field.label() == Label::LABEL_REPEATED;
+            let is_scalar = matches!(
+                field.type_(),
+                Type::TYPE_INT32
+                    | Type::TYPE_INT64
+                    | Type::TYPE_UINT32
+                    | Type::TYPE_UINT64
+                    | Type::TYPE_SINT32
+                    | Type::TYPE_SINT64
+                    | Type::TYPE_BOOL
+                    | Type::TYPE_ENUM
+                    | Type::TYPE_FIXED32
+                    | Type::TYPE_SFIXED32
+                    | Type::TYPE_FLOAT
+                    | Type::TYPE_FIXED64
+                    | Type::TYPE_SFIXED64
+                    | Type::TYPE_DOUBLE
+            );
+
+            let is_packed =
+                (is_repeated && is_scalar && !field.options.has_packed()) || field.options.packed();
+
             out.messages.entry(full_name.clone()).or_default().insert(
                 field.name().to_string(),
                 MessageField {
                     field_number: field.number() as u32,
-                    wire_type: field.type_().into(),
+                    wire_type: if is_packed {
+                        WireType::LengthDelimited
+                    } else {
+                        field.type_().into()
+                    },
                     xor_const: xor_const_field,
                 },
             );
         }
 
-        // collect command ids
+        // collect command ids from message extension
         if let Some(command_id_field) = message
             .options
             .unknown_fields()
@@ -109,6 +144,40 @@ pub fn generate_json_registry(
             && let UnknownValueRef::Varint(varint) = command_id_field
         {
             out.command_ids.insert(full_name, varint as u16);
+            continue;
         };
+
+        // collect command ids from comment
+        if let Some(source_loc) = ctx.get_message_loc(i) {
+            let Some(comment) = if source_loc.has_leading_comments() {
+                source_loc.leading_comments().trim()
+            } else if source_loc.has_trailing_comments() {
+                source_loc.trailing_comments().trim()
+            } else {
+                continue;
+            }
+            .split("\n")
+            .map(str::trim)
+            .last() else {
+                continue;
+            };
+
+            let lowercased_comment = comment.to_lowercase();
+
+            // CmdId or CmdID
+            if lowercased_comment.starts_with("cmdid: ")
+                && let Ok(cmd_id) = comment[7..].parse::<u16>()
+            {
+                out.command_ids.insert(full_name, cmd_id);
+            }
+            // MessageId
+            else if lowercased_comment.starts_with("messageid: ")
+                && let Some(rest) = comment.get(10..)
+                && let Some(num_part) = rest.split_whitespace().next()
+                && let Ok(message_id) = num_part.parse::<u16>()
+            {
+                out.command_ids.insert(full_name, message_id);
+            }
+        }
     }
 }
diff --git a/src/generator/mod.rs b/src/generator/mod.rs
index 0e4a109..7bfd371 100644
--- a/src/generator/mod.rs
+++ b/src/generator/mod.rs
@@ -10,6 +10,7 @@ use std::io;
 use crate::generator::json_registry::{ProtoJsonRegistry, generate_json_registry};
 
 mod json_registry;
+mod utils;
 
 pub fn generate(input: &[u8]) -> io::Result<CodeGeneratorResponse> {
     let codegen_request = CodeGeneratorRequest::parse_from_bytes(input)?;
@@ -24,7 +25,7 @@ pub fn generate(input: &[u8]) -> io::Result<CodeGeneratorResponse> {
         }
 
         let mut out = ProtoJsonRegistry::default();
-        generate_json_registry(&proto.message_type, proto.package(), None, &mut out);
+        generate_json_registry(&proto, &proto.message_type, proto.package(), None, &mut out);
 
         let mut json_file = File::new();
         json_file.set_content(serde_json::to_string_pretty(&out).unwrap());
diff --git a/src/generator/utils.rs b/src/generator/utils.rs
new file mode 100644
index 0000000..3fe0e54
--- /dev/null
+++ b/src/generator/utils.rs
@@ -0,0 +1,27 @@
+use protobuf::descriptor::{FileDescriptorProto, source_code_info::Location};
+
+pub struct SourceContext<'a> {
+    location_map: std::collections::HashMap<Vec<i32>, &'a Location>,
+}
+
+impl<'a> SourceContext<'a> {
+    pub fn new(file: &'a FileDescriptorProto) -> Self {
+        let mut map = std::collections::HashMap::new();
+        for loc in &file.source_code_info.location {
+            map.insert(loc.path.clone(), loc);
+        }
+        Self { location_map: map }
+    }
+
+    pub fn get_message_loc(&self, msg_index: usize) -> Option<&Location> {
+        self.location_map.get(&vec![4, msg_index as i32]).copied()
+    }
+
+    #[expect(unused)]
+    pub fn get_nested_loc(&self, parent_path: &[i32], nested_index: usize) -> Option<&Location> {
+        let mut path = parent_path.to_vec();
+        path.push(3);
+        path.push(nested_index as i32);
+        self.location_map.get(&path).copied()
+    }
+}