diff --git a/plugin-server/src/cdp/hog-watcher.ts b/plugin-server/src/cdp/hog-watcher.ts
index 4d7a16c5146f1..c40c86b0abc1c 100644
--- a/plugin-server/src/cdp/hog-watcher.ts
+++ b/plugin-server/src/cdp/hog-watcher.ts
@@ -29,9 +29,24 @@ export class HogWatcher {
         })
 
         this.observations[id] = update(observation)
+        this.observations[id].rating = this.calculateRating(this.observations[id])
         console.log('Observation updated', id, this.observations[id])
     }
 
+    private calculateRating(observation: HogWatcherObservation): number {
+        // Rating is from 0 to 1
+        // 1 - Function is working perfectly
+        // 0 - Function is not working at all
+
+        const totalInvocations = observation.successes + observation.failures
+        const totalAsyncInvocations = observation.asyncFunctionSuccesses + observation.asyncFunctionFailures
+
+        const successRate = totalInvocations ? observation.successes / totalInvocations : 1
+        const asyncSuccessRate = totalAsyncInvocations ? observation.asyncFunctionSuccesses / totalAsyncInvocations : 1
+
+        return Math.min(1, successRate, asyncSuccessRate)
+    }
+
     observeResults(results: HogFunctionInvocationResult[]) {
         // TODO: Actually measure something and store the result
         results.forEach((result) => {