diff --git a/packages/spec/src/data/object.zod.ts b/packages/spec/src/data/object.zod.ts
index f24c973d0..22a991f60 100644
--- a/packages/spec/src/data/object.zod.ts
+++ b/packages/spec/src/data/object.zod.ts
@@ -97,14 +97,14 @@ const ObjectSchemaBase = z.object({
    * Taxonomy & Organization
    */
   tags: z.array(z.string()).optional().describe('Categorization tags (e.g. "sales", "system", "reference")'),
-  active: z.boolean().default(true).describe('Is the object active and usable'),
-  isSystem: z.boolean().default(false).describe('Is system object (protected from deletion)'),
-  abstract: z.boolean().default(false).describe('Is abstract base object (cannot be instantiated)'),
+  active: z.boolean().optional().default(true).describe('Is the object active and usable'),
+  isSystem: z.boolean().optional().default(false).describe('Is system object (protected from deletion)'),
+  abstract: z.boolean().optional().default(false).describe('Is abstract base object (cannot be instantiated)'),
 
   /** 
    * Storage & Virtualization 
    */
-  datasource: z.string().default('default').describe('Target Datasource ID. "default" is the primary DB.'),
+  datasource: z.string().optional().default('default').describe('Target Datasource ID. "default" is the primary DB.'),
   tableName: z.string().optional().describe('Physical table/collection name in the target datasource'),
   
   /** 
diff --git a/packages/spec/src/stack.zod.ts b/packages/spec/src/stack.zod.ts
index 13689668c..1ae52ef35 100644
--- a/packages/spec/src/stack.zod.ts
+++ b/packages/spec/src/stack.zod.ts
@@ -105,8 +105,9 @@ export type ObjectStack = ObjectStackDefinition;
 
 /**
  * Type-safe helper to define a project configuration.
+ * Uses input type to allow optional fields with defaults.
  */
-export const defineStack = (config: ObjectStackDefinition) => config;
+export const defineStack = (config: z.input<typeof ObjectStackDefinitionSchema>) => config;
 
 
 /**
diff --git a/packages/spec/src/ui/app.zod.ts b/packages/spec/src/ui/app.zod.ts
index bd5e9d24c..72894e7c5 100644
--- a/packages/spec/src/ui/app.zod.ts
+++ b/packages/spec/src/ui/app.zod.ts
@@ -150,10 +150,10 @@ export const AppSchema = z.object({
   branding: AppBrandingSchema.optional().describe('App-specific branding'),
   
   /** Application status */
-  active: z.boolean().default(true).describe('Whether the app is enabled'),
+  active: z.boolean().optional().default(true).describe('Whether the app is enabled'),
 
   /** Is this the default app for new users? */
-  isDefault: z.boolean().default(false).describe('Is default app'),
+  isDefault: z.boolean().optional().default(false).describe('Is default app'),
   
   /** 
    * Navigation Tree Structure.