diff --git a/packages/server-api/src/deltas.test.ts b/packages/server-api/src/deltas.test.ts
new file mode 100644
index 000000000..535231765
--- /dev/null
+++ b/packages/server-api/src/deltas.test.ts
@@ -0,0 +1,59 @@
+import { Delta, Path } from './deltas'
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+const metaDelta: Delta = {
+  updates: [
+    {
+      meta: [
+        {
+          path: 'foo.bar' as Path,
+          value: {
+            displayName: 'Foo Bar'
+          }
+        }
+      ]
+    }
+  ]
+}
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+const valuesDelta: Delta = {
+  updates: [
+    {
+      values: [
+        {
+          path: 'foo.bar' as Path,
+          value: {
+            displayName: 'Foo Bar'
+          }
+        }
+      ]
+    }
+  ]
+}
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+const combinedDelta: Delta = {
+  updates: [
+    {
+      meta: [
+        {
+          path: 'foo.bar' as Path,
+          value: {
+            displayName: 'Foo Bar'
+          }
+        }
+      ]
+    },
+    {
+      values: [
+        {
+          path: 'foo.bar' as Path,
+          value: {
+            displayName: 'Foo Bar'
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/packages/server-api/src/deltas.ts b/packages/server-api/src/deltas.ts
index 2e60078bd..e8e5320ff 100644
--- a/packages/server-api/src/deltas.ts
+++ b/packages/server-api/src/deltas.ts
@@ -32,25 +32,25 @@ export interface DeltaSubscription {
   }>
 }
 
-// "Classic" Delta with values
-export interface ValuesDelta {
+export interface Delta {
   context?: Context
   updates: Update[]
 }
 
-export interface MetaDelta {
-  metas: Array<{ values: Meta[] }>
-}
-
-// Delta Message
-export type Delta = ValuesDelta | MetaDelta
+/**
+ * @deprecated earlier mistake assumed ValuesDelta and MetaDelta were separate
+ */
+export type ValuesDelta = Delta
+/**
+ * @deprecated earlier mistake assumed ValuesDelta and MetaDelta were separate
+ */
+export type MetaDelta = Delta
 
-export interface Update {
+export type Update = {
   timestamp?: Timestamp
   source?: Source
   $source?: SourceRef
-  values: PathValue[]
-}
+} & ({ values: PathValue[] } | { meta: Meta[] }) // require either values or meta or both
 
 // Update delta
 export interface PathValue {
@@ -67,15 +67,26 @@ export interface Notification {
 
 // MetaMessage
 export interface Meta {
-  path: string
+  path: Path
   value: MetaValue
 }
 
 // Meta payload
 export interface MetaValue {
-  description: string
+  description?: string
   units?: string
   example?: string
+  timeout?: number
+  displayName?: string
+  displayScale?: {
+    lower: number
+    upper: number
+  }
+  zones?: {
+    upper: number
+    lower: number
+    state: string
+  }[]
 }
 
 // Notification attribute types
diff --git a/packages/server-api/tsconfig.json b/packages/server-api/tsconfig.json
index 5023d43d6..0bad7084f 100644
--- a/packages/server-api/tsconfig.json
+++ b/packages/server-api/tsconfig.json
@@ -69,5 +69,6 @@
   },
   "ts-node": {
     "files": true
-  }
+  },
+  "exclude": ["src/**/*.test.ts"]
 }