diff --git a/manifest.json b/manifest.json
index adc5aec..051490b 100644
--- a/manifest.json
+++ b/manifest.json
@@ -84,12 +84,34 @@
       {
         "url": "https://oauth.platform.intuit.com/oauth2/v1/.*",
         "methods": ["POST"],
-        "timeout": 20
+        "timeout": 20,
+        "settingsInjection": {
+          "client_id": {
+            "header": ["Authorization"]
+          },
+          "client_secret": {
+            "header": ["Authorization"]
+          },
+          "integration_key": {
+            "header": ["Authorization"]
+          },
+          "secret_key": {
+            "header": ["Authorization"]
+          }
+        }
       },
       {
         "url": "https://developer.api.intuit.com/v2/oauth2/tokens/revoke",
         "methods": ["POST"],
-        "timeout": 20
+        "timeout": 20,
+        "settingsInjection": {
+          "client_id": {
+            "header": ["Authorization"]
+          },
+          "client_secret": {
+            "header": ["Authorization"]
+          }
+        }
       }
     ]
   }
diff --git a/src/constants.ts b/src/constants.ts
index 8fe6b61..5e65228 100644
--- a/src/constants.ts
+++ b/src/constants.ts
@@ -6,7 +6,7 @@ export const placeholders = {
     OAUTH2_ACCESS_TOKEN_PATH: 'oauth2/access_token',
     OAUTH2_REFRESH_TOKEN_PATH: 'oauth2/refresh_token',
     IS_USING_SANDBOX: 'is_using_sandbox',
-};
+} as const;
 
 export const GLOBAL_CLIENT_ID = 'ABvWsXjB1yre80UrAXj7uDaWUOWPiW7CZ04t0BJgM75UJZYxJ8';