diff --git a/src/ast/lang/property_validator_language.nim b/src/ast/lang/property_validator_language.nim
index e884395d..06f94c33 100644
--- a/src/ast/lang/property_validator_language.nim
+++ b/src/ast/lang/property_validator_language.nim
@@ -2,6 +2,7 @@ import std/[tables, strformat, options, json]
 import misc/[id, util, custom_logger, custom_async]
 import ui/node
 import ast/[model, cells, cell_builder_database, base_language]
+import workspaces/[workspace]
 import lang_language, cell_language
 
 export id, ast_ids
@@ -31,36 +32,36 @@ scopeComputers[IdPropertyValidatorDefinition] = proc(ctx: ModelComputationContex
 
   return nodes
 
-var propertyValidatorLanguage*: Future[Language] = nil
-proc createPropertyValidatorLanguage(): Future[Language] {.async.} =
-  let cellLanguage =  cell_language.cellLanguage.await
+proc resolveLanguage(project: Project, workspace: WorkspaceFolder, id: LanguageId): Future[Option[Language]] {.async.} =
+  if id == IdLangLanguage:
+    assert lang_language.langLanguage.isNotNil
+    return lang_language.langLanguage.some
+  if id == IdCellLanguage:
+    let cellLanguage =  cell_language.cellLanguage.await
+    assert cellLanguage.isNotNil
+    return cellLanguage.some
+  if id == IdBaseInterfaces:
+    assert base_language.baseInterfaces.isNotNil
+    return base_language.baseInterfaces.some
+  else:
+    log lvlError, "createPropertyValidatorLanguage::resolveLanguage: unknown language id: ", id
 
-  proc resolveLanguage(id: LanguageId): Option[Language] =
-    if id == IdLangLanguage:
-      assert lang_language.langLanguage.isNotNil
-      return lang_language.langLanguage.some
-    if id == IdCellLanguage:
-      assert cellLanguage.isNotNil
-      return cellLanguage.some
-    if id == IdBaseInterfaces:
-      assert base_language.baseInterfaces.isNotNil
-      return base_language.baseInterfaces.some
-    else:
-      log lvlError, "createPropertyValidatorLanguage::resolveLanguage: unknown language id: ", id
+proc resolveModel(project: Project, workspace: WorkspaceFolder, id: ModelId): Future[Option[Model]] {.async.} =
+  assert baseInterfacesModel.isNotNil
+  if id == baseInterfacesModel.id:
+    return baseInterfacesModel.some
+  if id == baseLanguageModel.id:
+    return baseLanguageModel.some
+  log lvlError, fmt"createPropertyValidatorLanguage::resolveModel: unknown model id: {id}"
 
-  proc resolveModel(project: Project, id: ModelId): Option[Model] =
-    assert baseInterfacesModel.isNotNil
-    if id == baseInterfacesModel.id:
-      return baseInterfacesModel.some
-    if id == baseLanguageModel.id:
-      return baseLanguageModel.some
-    log lvlError, fmt"createPropertyValidatorLanguage::resolveModel: unknown model id: {id}"
+var propertyValidatorLanguage*: Future[Language] = nil
+proc createPropertyValidatorLanguage(): Future[Language] {.async.} =
 
   let model = newModel(IdPropertyValidatorLanguage.ModelId)
   model.addLanguage(lang_language.langLanguage)
 
   const jsonText = staticRead "../model/lang/property-validator.ast-model"
-  if not model.loadFromJson("model/lang/property-validator.ast-model", jsonText.parseJson, resolveLanguage, resolveModel):
+  if not model.loadFromJsonAsync(nil, nil, "model/lang/property-validator.ast-model", jsonText.parseJson, resolveLanguage, resolveModel).await:
     log lvlError, "Failed to load property validator model"
     return Language nil
 
diff --git a/src/ast/model.nim b/src/ast/model.nim
index 410abe95..59173cc3 100644
--- a/src/ast/model.nim
+++ b/src/ast/model.nim
@@ -1289,16 +1289,17 @@ proc loadFromJson*(project: Project, json: JsonNode, opt = Joptions()): bool =
 proc loadFromJsonAsync*(model: Model, project: Project, workspace: WorkspaceFolder, path: string, json: JsonNode,
   resolveLanguage: proc(project: Project, workspace: WorkspaceFolder, id: LanguageId): Future[Option[Language]],
   resolveModel: proc(project: Project, workspace: WorkspaceFolder, id: ModelId): Future[Option[Model]],
-  opt = Joptions()): Future[void] {.async.} =
+  opt = Joptions()): Future[bool] {.async.} =
   model.path = path
   if json.kind != JObject:
     log(lvlError, fmt"Expected JObject")
-    return
+    return false
 
   if json.hasKey("id"):
     model.id = json["id"].jsonTo ModelId
   else:
     log(lvlError, fmt"Missing id")
+    return false
 
   if json.hasKey("languages"):
     for languageIdJson in json["languages"]:
@@ -1307,6 +1308,7 @@ proc loadFromJsonAsync*(model: Model, project: Project, workspace: WorkspaceFold
         model.addLanguage(language)
       else:
         log(lvlError, fmt"Unknown language {id}")
+        return false
   else:
     log(lvlWarn, fmt"Missing languages")
 
@@ -1318,6 +1320,7 @@ proc loadFromJsonAsync*(model: Model, project: Project, workspace: WorkspaceFold
         model.addImport(m)
       else:
         log(lvlError, fmt"Unknown model {id}")
+        return false
 
   if json.hasKey("rootNodes"):
     for node in json["rootNodes"]:
@@ -1325,9 +1328,12 @@ proc loadFromJsonAsync*(model: Model, project: Project, workspace: WorkspaceFold
         model.addRootNode(node)
       else:
         log(lvlError, fmt"Failed to parse root node from json")
+        return false
   else:
     log(lvlWarn, fmt"Missing root nodes")
 
+  return true
+
 proc loadFromJson*(model: Model, path: string, json: JsonNode,
   resolveLanguage: proc(id: LanguageId): Option[Language],
   resolveModel: proc(project: Project, id: ModelId): Option[Model],
diff --git a/src/ast/model_document.nim b/src/ast/model_document.nim
index c8b2ac06..1bc1255d 100644
--- a/src/ast/model_document.nim
+++ b/src/ast/model_document.nim
@@ -572,8 +572,7 @@ proc loadModelAsync(project: Project, ws: WorkspaceFolder, path: string): Future
   let json = jsonText.parseJson
 
   var model = newModel()
-  await model.loadFromJsonAsync(project, ws, path, json, resolveLanguage, resolveModel)
-  if model.id.isNone:
+  if not model.loadFromJsonAsync(project, ws, path, json, resolveLanguage, resolveModel).await:
     log lvlError, fmt"Failed to load model: no id"
     return Model.none