diff --git a/grammar.js b/grammar.js
index ed9f7a7..7f9cb5a 100644
--- a/grammar.js
+++ b/grammar.js
@@ -14,12 +14,14 @@ module.exports = grammar({
         $.service_declaration,
         $.enum_declaration,
       ),
-    type_declaration: ($) => seq("type", $.identifier, optional($.attributes)),
+    type_declaration: ($) =>
+      seq("type", field("name", $.identifier), optional($.attributes)),
     attributes: ($) =>
       seq("{", optional(seq($.attribute, repeat($.attribute))), "}"),
     attribute: ($) => seq($.pair, ";"),
 
-    enum_declaration: ($) => seq("enum", $.identifier, $.enum_values),
+    enum_declaration: ($) =>
+      seq("enum", field("name", $.identifier), $.enum_values),
     enum_values: ($) =>
       seq(
         "{",
@@ -32,12 +34,17 @@ module.exports = grammar({
     enum_value_declaration: ($) => seq($.identifier),
 
     define_declaration: ($) =>
-      seq("define", $.identifier, choice($.string, $.identifier), ";"),
+      seq(
+        "define",
+        field("key", $.identifier),
+        field("value", choice($.string, $.identifier)),
+        ";",
+      ),
 
-    import_declaration: ($) => seq("import", $.string, ";"),
+    import_declaration: ($) => seq("import", field("source", $.string), ";"),
 
     service_declaration: ($) =>
-      seq("service", $.identifier, $.service_functions),
+      seq("service", field("name", $.identifier), $.service_functions),
 
     service_functions: ($) =>
       seq(
@@ -53,7 +60,8 @@ module.exports = grammar({
         "}",
       ),
 
-    function_decorator: ($) => seq("@", $.identifier, $.decorator_arguments),
+    function_decorator: ($) =>
+      seq("@", field("name", $.identifier), $.decorator_arguments),
     decorator_arguments: ($) =>
       seq(
         "(",
@@ -84,11 +92,7 @@ module.exports = grammar({
         ")",
       ),
     function_argument: ($) =>
-      seq(
-        field("argument_identifier", $.identifier),
-        ":",
-        field("argument_type", $.type),
-      ),
+      seq(field("name", $.identifier), ":", field("type", $.type)),
 
     pair: ($) =>
       seq(
diff --git a/src/grammar.json b/src/grammar.json
index 0a52897..d3e7477 100644
--- a/src/grammar.json
+++ b/src/grammar.json
@@ -41,8 +41,12 @@
           "value": "type"
         },
         {
-          "type": "SYMBOL",
-          "name": "identifier"
+          "type": "FIELD",
+          "name": "name",
+          "content": {
+            "type": "SYMBOL",
+            "name": "identifier"
+          }
         },
         {
           "type": "CHOICE",
@@ -116,8 +120,12 @@
           "value": "enum"
         },
         {
-          "type": "SYMBOL",
-          "name": "identifier"
+          "type": "FIELD",
+          "name": "name",
+          "content": {
+            "type": "SYMBOL",
+            "name": "identifier"
+          }
         },
         {
           "type": "SYMBOL",
@@ -218,21 +226,29 @@
           "value": "define"
         },
         {
-          "type": "SYMBOL",
-          "name": "identifier"
+          "type": "FIELD",
+          "name": "key",
+          "content": {
+            "type": "SYMBOL",
+            "name": "identifier"
+          }
         },
         {
-          "type": "CHOICE",
-          "members": [
-            {
-              "type": "SYMBOL",
-              "name": "string"
-            },
-            {
-              "type": "SYMBOL",
-              "name": "identifier"
-            }
-          ]
+          "type": "FIELD",
+          "name": "value",
+          "content": {
+            "type": "CHOICE",
+            "members": [
+              {
+                "type": "SYMBOL",
+                "name": "string"
+              },
+              {
+                "type": "SYMBOL",
+                "name": "identifier"
+              }
+            ]
+          }
         },
         {
           "type": "STRING",
@@ -248,8 +264,12 @@
           "value": "import"
         },
         {
-          "type": "SYMBOL",
-          "name": "string"
+          "type": "FIELD",
+          "name": "source",
+          "content": {
+            "type": "SYMBOL",
+            "name": "string"
+          }
         },
         {
           "type": "STRING",
@@ -265,8 +285,12 @@
           "value": "service"
         },
         {
-          "type": "SYMBOL",
-          "name": "identifier"
+          "type": "FIELD",
+          "name": "name",
+          "content": {
+            "type": "SYMBOL",
+            "name": "identifier"
+          }
         },
         {
           "type": "SYMBOL",
@@ -331,8 +355,12 @@
           "value": "@"
         },
         {
-          "type": "SYMBOL",
-          "name": "identifier"
+          "type": "FIELD",
+          "name": "name",
+          "content": {
+            "type": "SYMBOL",
+            "name": "identifier"
+          }
         },
         {
           "type": "SYMBOL",
@@ -511,7 +539,7 @@
       "members": [
         {
           "type": "FIELD",
-          "name": "argument_identifier",
+          "name": "name",
           "content": {
             "type": "SYMBOL",
             "name": "identifier"
@@ -523,7 +551,7 @@
         },
         {
           "type": "FIELD",
-          "name": "argument_type",
+          "name": "type",
           "content": {
             "type": "SYMBOL",
             "name": "type"
diff --git a/src/node-types.json b/src/node-types.json
index c6698f4..4b07ca6 100644
--- a/src/node-types.json
+++ b/src/node-types.json
@@ -66,20 +66,31 @@
   {
     "type": "define_declaration",
     "named": true,
-    "fields": {},
-    "children": {
-      "multiple": true,
-      "required": true,
-      "types": [
-        {
-          "type": "identifier",
-          "named": true
-        },
-        {
-          "type": "string",
-          "named": true
-        }
-      ]
+    "fields": {
+      "key": {
+        "multiple": false,
+        "required": true,
+        "types": [
+          {
+            "type": "identifier",
+            "named": true
+          }
+        ]
+      },
+      "value": {
+        "multiple": false,
+        "required": true,
+        "types": [
+          {
+            "type": "identifier",
+            "named": true
+          },
+          {
+            "type": "string",
+            "named": true
+          }
+        ]
+      }
     }
   },
   {
@@ -116,18 +127,25 @@
   {
     "type": "enum_declaration",
     "named": true,
-    "fields": {},
+    "fields": {
+      "name": {
+        "multiple": false,
+        "required": true,
+        "types": [
+          {
+            "type": "identifier",
+            "named": true
+          }
+        ]
+      }
+    },
     "children": {
-      "multiple": true,
+      "multiple": false,
       "required": true,
       "types": [
         {
           "type": "enum_values",
           "named": true
-        },
-        {
-          "type": "identifier",
-          "named": true
         }
       ]
     }
@@ -189,7 +207,7 @@
     "type": "function_argument",
     "named": true,
     "fields": {
-      "argument_identifier": {
+      "name": {
         "multiple": false,
         "required": true,
         "types": [
@@ -199,7 +217,7 @@
           }
         ]
       },
-      "argument_type": {
+      "type": {
         "multiple": false,
         "required": true,
         "types": [
@@ -229,18 +247,25 @@
   {
     "type": "function_decorator",
     "named": true,
-    "fields": {},
+    "fields": {
+      "name": {
+        "multiple": false,
+        "required": true,
+        "types": [
+          {
+            "type": "identifier",
+            "named": true
+          }
+        ]
+      }
+    },
     "children": {
-      "multiple": true,
+      "multiple": false,
       "required": true,
       "types": [
         {
           "type": "decorator_arguments",
           "named": true
-        },
-        {
-          "type": "identifier",
-          "named": true
         }
       ]
     }
@@ -248,16 +273,17 @@
   {
     "type": "import_declaration",
     "named": true,
-    "fields": {},
-    "children": {
-      "multiple": false,
-      "required": true,
-      "types": [
-        {
-          "type": "string",
-          "named": true
-        }
-      ]
+    "fields": {
+      "source": {
+        "multiple": false,
+        "required": true,
+        "types": [
+          {
+            "type": "string",
+            "named": true
+          }
+        ]
+      }
     }
   },
   {
@@ -318,15 +344,22 @@
   {
     "type": "service_declaration",
     "named": true,
-    "fields": {},
+    "fields": {
+      "name": {
+        "multiple": false,
+        "required": true,
+        "types": [
+          {
+            "type": "identifier",
+            "named": true
+          }
+        ]
+      }
+    },
     "children": {
-      "multiple": true,
+      "multiple": false,
       "required": true,
       "types": [
-        {
-          "type": "identifier",
-          "named": true
-        },
         {
           "type": "service_functions",
           "named": true
@@ -468,18 +501,25 @@
   {
     "type": "type_declaration",
     "named": true,
-    "fields": {},
+    "fields": {
+      "name": {
+        "multiple": false,
+        "required": true,
+        "types": [
+          {
+            "type": "identifier",
+            "named": true
+          }
+        ]
+      }
+    },
     "children": {
-      "multiple": true,
-      "required": true,
+      "multiple": false,
+      "required": false,
       "types": [
         {
           "type": "attributes",
           "named": true
-        },
-        {
-          "type": "identifier",
-          "named": true
         }
       ]
     }
diff --git a/src/parser.c b/src/parser.c
index e4fdc74..327fda7 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -13,7 +13,7 @@
 #define EXTERNAL_TOKEN_COUNT 0
 #define FIELD_COUNT 7
 #define MAX_ALIAS_SEQUENCE_LENGTH 5
-#define PRODUCTION_ID_COUNT 6
+#define PRODUCTION_ID_COUNT 9
 
 enum ts_symbol_identifiers {
   anon_sym_type = 1,
@@ -468,48 +468,58 @@ static const TSSymbolMetadata ts_symbol_metadata[] = {
 };
 
 enum ts_field_identifiers {
-  field_argument_identifier = 1,
-  field_argument_type = 2,
-  field_key = 3,
-  field_name = 4,
-  field_parameters = 5,
-  field_return_type = 6,
+  field_key = 1,
+  field_name = 2,
+  field_parameters = 3,
+  field_return_type = 4,
+  field_source = 5,
+  field_type = 6,
   field_value = 7,
 };
 
 static const char * const ts_field_names[] = {
   [0] = NULL,
-  [field_argument_identifier] = "argument_identifier",
-  [field_argument_type] = "argument_type",
   [field_key] = "key",
   [field_name] = "name",
   [field_parameters] = "parameters",
   [field_return_type] = "return_type",
+  [field_source] = "source",
+  [field_type] = "type",
   [field_value] = "value",
 };
 
 static const TSFieldMapSlice ts_field_map_slices[PRODUCTION_ID_COUNT] = {
-  [1] = {.index = 0, .length = 2},
-  [2] = {.index = 2, .length = 2},
-  [3] = {.index = 4, .length = 2},
-  [4] = {.index = 6, .length = 2},
-  [5] = {.index = 8, .length = 3},
+  [1] = {.index = 0, .length = 1},
+  [2] = {.index = 1, .length = 1},
+  [3] = {.index = 2, .length = 2},
+  [4] = {.index = 4, .length = 2},
+  [5] = {.index = 6, .length = 2},
+  [6] = {.index = 8, .length = 2},
+  [7] = {.index = 10, .length = 2},
+  [8] = {.index = 12, .length = 3},
 };
 
 static const TSFieldMapEntry ts_field_map_entries[] = {
   [0] =
+    {field_name, 1},
+  [1] =
+    {field_source, 1},
+  [2] =
+    {field_key, 1},
+    {field_value, 2},
+  [4] =
     {field_key, 0},
     {field_value, 2},
-  [2] =
+  [6] =
     {field_key, 0},
     {field_value, 3},
-  [4] =
+  [8] =
     {field_name, 1},
     {field_parameters, 2},
-  [6] =
-    {field_argument_identifier, 0},
-    {field_argument_type, 2},
-  [8] =
+  [10] =
+    {field_name, 0},
+    {field_type, 2},
+  [12] =
     {field_name, 0},
     {field_parameters, 1},
     {field_return_type, 3},
@@ -2323,21 +2333,21 @@ static const TSParseActionEntry ts_parse_actions[] = {
   [52] = {.entry = {.count = 2, .reusable = true}}, REDUCE(aux_sym_service_functions_repeat2, 2, 0, 0), SHIFT_REPEAT(86),
   [55] = {.entry = {.count = 2, .reusable = false}}, REDUCE(aux_sym_service_functions_repeat2, 2, 0, 0), SHIFT_REPEAT(87),
   [58] = {.entry = {.count = 2, .reusable = false}}, REDUCE(aux_sym_service_functions_repeat2, 2, 0, 0), SHIFT_REPEAT(80),
-  [61] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_type_declaration, 2, 0, 0),
+  [61] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_type_declaration, 2, 0, 1),
   [63] = {.entry = {.count = 1, .reusable = true}}, SHIFT(43),
   [65] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_attributes, 3, 0, 0),
   [67] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_enum_values, 4, 0, 0),
   [69] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_enum_values, 3, 0, 0),
-  [71] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_type_declaration, 3, 0, 0),
-  [73] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_enum_declaration, 3, 0, 0),
-  [75] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_import_declaration, 3, 0, 0),
+  [71] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_type_declaration, 3, 0, 1),
+  [73] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_enum_declaration, 3, 0, 1),
+  [75] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_import_declaration, 3, 0, 2),
   [77] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_service_functions, 2, 0, 0),
-  [79] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_service_declaration, 3, 0, 0),
+  [79] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_service_declaration, 3, 0, 1),
   [81] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_attributes, 2, 0, 0),
   [83] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_service_functions, 3, 0, 0),
   [85] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_enum_values, 2, 0, 0),
   [87] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_attributes, 4, 0, 0),
-  [89] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_define_declaration, 4, 0, 0),
+  [89] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_define_declaration, 4, 0, 3),
   [91] = {.entry = {.count = 1, .reusable = true}}, SHIFT(24),
   [93] = {.entry = {.count = 1, .reusable = true}}, SHIFT(55),
   [95] = {.entry = {.count = 1, .reusable = true}}, REDUCE(aux_sym_attributes_repeat1, 2, 0, 0),
@@ -2352,8 +2362,8 @@ static const TSParseActionEntry ts_parse_actions[] = {
   [115] = {.entry = {.count = 1, .reusable = false}}, REDUCE(aux_sym_service_functions_repeat1, 2, 0, 0),
   [117] = {.entry = {.count = 1, .reusable = false}}, SHIFT(49),
   [119] = {.entry = {.count = 1, .reusable = true}}, SHIFT(42),
-  [121] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_service_function, 5, 0, 5),
-  [123] = {.entry = {.count = 1, .reusable = false}}, REDUCE(sym_service_function, 5, 0, 5),
+  [121] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_service_function, 5, 0, 8),
+  [123] = {.entry = {.count = 1, .reusable = false}}, REDUCE(sym_service_function, 5, 0, 8),
   [125] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_array_type, 2, 0, 0),
   [127] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_map_type, 5, 0, 0),
   [129] = {.entry = {.count = 1, .reusable = false}}, SHIFT(48),
@@ -2362,12 +2372,12 @@ static const TSParseActionEntry ts_parse_actions[] = {
   [135] = {.entry = {.count = 1, .reusable = false}}, REDUCE(aux_sym__string_content, 2, 0, 0),
   [137] = {.entry = {.count = 2, .reusable = true}}, REDUCE(aux_sym__string_content, 2, 0, 0), SHIFT_REPEAT(42),
   [140] = {.entry = {.count = 1, .reusable = true}}, SHIFT(22),
-  [142] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_service_notification, 4, 0, 3),
-  [144] = {.entry = {.count = 1, .reusable = false}}, REDUCE(sym_service_notification, 4, 0, 3),
+  [142] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_service_notification, 4, 0, 6),
+  [144] = {.entry = {.count = 1, .reusable = false}}, REDUCE(sym_service_notification, 4, 0, 6),
   [146] = {.entry = {.count = 1, .reusable = true}}, SHIFT(78),
   [148] = {.entry = {.count = 1, .reusable = true}}, SHIFT(57),
-  [150] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_function_decorator, 3, 0, 0),
-  [152] = {.entry = {.count = 1, .reusable = false}}, REDUCE(sym_function_decorator, 3, 0, 0),
+  [150] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_function_decorator, 3, 0, 1),
+  [152] = {.entry = {.count = 1, .reusable = false}}, REDUCE(sym_function_decorator, 3, 0, 1),
   [154] = {.entry = {.count = 1, .reusable = true}}, SHIFT(62),
   [156] = {.entry = {.count = 1, .reusable = true}}, SHIFT(40),
   [158] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_string, 2, 0, 0),
@@ -2404,7 +2414,7 @@ static const TSParseActionEntry ts_parse_actions[] = {
   [223] = {.entry = {.count = 1, .reusable = true}}, SHIFT(53),
   [225] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_function_arguments, 4, 0, 0),
   [227] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_function_arguments, 2, 0, 0),
-  [229] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_function_argument, 3, 0, 4),
+  [229] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_function_argument, 3, 0, 7),
   [231] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_attribute, 2, 0, 0),
   [233] = {.entry = {.count = 1, .reusable = true}}, SHIFT(27),
   [235] = {.entry = {.count = 1, .reusable = true}}, SHIFT(9),
@@ -2416,12 +2426,12 @@ static const TSParseActionEntry ts_parse_actions[] = {
   [247] = {.entry = {.count = 1, .reusable = true}}, SHIFT(71),
   [249] = {.entry = {.count = 1, .reusable = true}}, SHIFT(26),
   [251] = {.entry = {.count = 1, .reusable = true}}, SHIFT(36),
-  [253] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_pair, 4, 0, 2),
+  [253] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_pair, 4, 0, 5),
   [255] = {.entry = {.count = 1, .reusable = true}}, SHIFT(8),
   [257] = {.entry = {.count = 1, .reusable = true}}, SHIFT(19),
   [259] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_map_key_type, 1, 0, 0),
   [261] = {.entry = {.count = 1, .reusable = true}}, SHIFT(6),
-  [263] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_pair, 3, 0, 1),
+  [263] = {.entry = {.count = 1, .reusable = true}}, REDUCE(sym_pair, 3, 0, 4),
   [265] = {.entry = {.count = 1, .reusable = true}}, SHIFT(44),
   [267] = {.entry = {.count = 1, .reusable = true}},  ACCEPT_INPUT(),
   [269] = {.entry = {.count = 1, .reusable = true}}, SHIFT(79),