diff --git a/src/api/coral.ts b/src/api/coral.ts
index 2ef3e5e..5851bb6 100644
--- a/src/api/coral.ts
+++ b/src/api/coral.ts
@@ -56,6 +56,10 @@ export default class CoralApi {
 
         debug('fetch %s %s, response %s', method, url, response.status);
 
+        if (response.status !== 200) {
+            throw new ErrorResponse('[znc] Non-200 status code', response, await response.text());
+        }
+
         const data = await response.json() as CoralResponse<T>;
 
         if (data.status === CoralStatus.TOKEN_EXPIRED && _autoRenewToken && !_attempt && this.onTokenExpired) {
diff --git a/src/api/moon.ts b/src/api/moon.ts
index 2395b07..615b938 100644
--- a/src/api/moon.ts
+++ b/src/api/moon.ts
@@ -49,6 +49,10 @@ export default class MoonApi {
 
         debug('fetch %s %s, response %s', method, url, response.status);
 
+        if (response.status !== 200) {
+            throw new ErrorResponse('[moon] Non-200 status code', response, await response.text());
+        }
+
         const data = await response.json() as T | MoonError;
 
         if ('errorCode' in data) {
diff --git a/src/api/nooklink.ts b/src/api/nooklink.ts
index c9cefa3..674f174 100644
--- a/src/api/nooklink.ts
+++ b/src/api/nooklink.ts
@@ -45,7 +45,7 @@ export default class NooklinkApi {
         debug('fetch %s %s, response %s', method, url, response.status);
 
         if (response.status !== 200 && response.status !== 201) {
-            throw new ErrorResponse('[nooklink] Unknown error', response, await response.text());
+            throw new ErrorResponse('[nooklink] Non-200/201 status code', response, await response.text());
         }
 
         const data = await response.json() as T | WebServiceError;
diff --git a/src/api/splatnet2.ts b/src/api/splatnet2.ts
index b016ad8..a7c1f97 100644
--- a/src/api/splatnet2.ts
+++ b/src/api/splatnet2.ts
@@ -53,7 +53,7 @@ export default class SplatNet2Api {
         debug('fetch %s %s, response %s', method, url, response.status);
 
         if (response.status !== 200) {
-            throw new ErrorResponse('[splatnet2] Unknown error', response, await response.text());
+            throw new ErrorResponse('[splatnet2] Non-200 status code', response, await response.text());
         }
 
         updateIksmSessionLastUsed.handler?.call(null, this.iksm_session);
diff --git a/src/api/znc-proxy.ts b/src/api/znc-proxy.ts
index 1a9850a..4a1fefb 100644
--- a/src/api/znc-proxy.ts
+++ b/src/api/znc-proxy.ts
@@ -44,7 +44,7 @@ export default class ZncProxyApi implements CoralApi {
         if (response.status === 204) return null!;
 
         if (response.status !== 200) {
-            throw new ErrorResponse('[zncproxy] Unknown error', response, await response.text());
+            throw new ErrorResponse('[zncproxy] Non-200/204 status code', response, await response.text());
         }
 
         const data = await response.json() as T;