diff --git a/Sources/GoogleAI/GenerativeModel.swift b/Sources/GoogleAI/GenerativeModel.swift
index 39fdbb8..4eb5caa 100644
--- a/Sources/GoogleAI/GenerativeModel.swift
+++ b/Sources/GoogleAI/GenerativeModel.swift
@@ -318,7 +318,7 @@ public final class GenerativeModel {
     if let error = error as? GenerateContentError {
       return error
     } else if let error = error as? RPCError, error.isInvalidAPIKeyError() {
-      return GenerateContentError.invalidAPIKey
+      return GenerateContentError.invalidAPIKey(message: error.message)
     } else if let error = error as? RPCError, error.isUnsupportedUserLocationError() {
       return GenerateContentError.unsupportedUserLocation
     }
diff --git a/Tests/GoogleAITests/GenerativeModelTests.swift b/Tests/GoogleAITests/GenerativeModelTests.swift
index 41f6844..5cd14d9 100644
--- a/Tests/GoogleAITests/GenerativeModelTests.swift
+++ b/Tests/GoogleAITests/GenerativeModelTests.swift
@@ -248,8 +248,8 @@ final class GenerativeModelTests: XCTestCase {
     do {
       _ = try await model.generateContent(testPrompt)
       XCTFail("Should throw GenerateContentError.internalError; no error thrown.")
-    } catch GenerateContentError.invalidAPIKey {
-      // Do nothing, catching a GenerateContentError.invalidAPIKey error is expected.
+    } catch let GenerateContentError.invalidAPIKey(message) {
+      XCTAssertEqual(message, "API key not valid. Please pass a valid API key.")
     } catch {
       XCTFail("Should throw GenerateContentError.invalidAPIKey; error thrown: \(error)")
     }