diff --git a/fern/apis/api/openapi.json b/fern/apis/api/openapi.json
index 1a6dfb2..98d78d5 100644
--- a/fern/apis/api/openapi.json
+++ b/fern/apis/api/openapi.json
@@ -15580,6 +15580,20 @@
           "clientSecret"
         ]
       },
+      "Oauth2AuthenticationSession": {
+        "type": "object",
+        "properties": {
+          "accessToken": {
+            "type": "string",
+            "description": "This is the OAuth2 access token."
+          },
+          "expiresAt": {
+            "format": "date-time",
+            "type": "string",
+            "description": "This is the OAuth2 access token expiration."
+          }
+        }
+      },
       "CustomLLMCredential": {
         "type": "object",
         "properties": {
@@ -15620,6 +15634,14 @@
             "type": "string",
             "description": "This is the ISO 8601 date-time string of when the assistant was last updated."
           },
+          "authenticationSession": {
+            "description": "This is the authentication session for the credential. Available for credentials that have an authentication plan.",
+            "allOf": [
+              {
+                "$ref": "#/components/schemas/Oauth2AuthenticationSession"
+              }
+            ]
+          },
           "name": {
             "type": "string",
             "description": "This is the name of credential. This is just for your reference.",
@@ -16928,6 +16950,14 @@
             "type": "string",
             "description": "This is the ISO 8601 date-time string of when the assistant was last updated."
           },
+          "authenticationSession": {
+            "description": "This is the authentication session for the credential. Available for credentials that have an authentication plan.",
+            "allOf": [
+              {
+                "$ref": "#/components/schemas/Oauth2AuthenticationSession"
+              }
+            ]
+          },
           "name": {
             "type": "string",
             "description": "This is the name of credential. This is just for your reference.",
@@ -16941,7 +16971,8 @@
           "id",
           "orgId",
           "createdAt",
-          "updatedAt"
+          "updatedAt",
+          "authenticationSession"
         ]
       },
       "XAiCredential": {