diff --git a/doc/releasenotes.md b/doc/releasenotes.md
index b0a7aada77e9be8c1053d08b6088476eaac7637c..e4e06cc98d1b523e9db035e3b6ec912213ea3b1f 100644
--- a/doc/releasenotes.md
+++ b/doc/releasenotes.md
@@ -5,7 +5,7 @@
 #### 3GPP CAPIF release 18
 
 - New endpoints included in new release 18 with new logic.
-- New logic to support ***Vendor Extensibility*** on Publish Service.
+- New logic to support ***Vendor Extensibility*** on Publish and Discover Service.
 - New logic to support ***API Status*** feature on Publish and Events Services.
 - Supported Features now are mandatory for all POST and PUT Requests as is described on TS 29.222.
     - **Possible Breaking change**, all POST request now must include supported features attribute, default can me set to "0" to keep all features inactive.
@@ -13,11 +13,61 @@
 
 ### **Technical Debt Solved**
 
+#### **Vendor Extensibility feature**
+
+- Publish API:
+    - On publishing a service API, **SupportedFeatures** is read and checked whether VendExt feature is enabled.
+    - When VendExt is enabled, vendor-specific fields are searched and stored in the db inside the ServiceAPIDescription object
+    - Vendor-specific fields are added according to the specific format:
+    ```
+    "vendorSpecific-urn:<organization>:<field name>": {
+        "key1": "value1",
+        ...
+        "keyN": "valueN",
+    }
+  
+    e.g. 
+    "vendorSpecific-urn:etsi:mec:capifext:transport-info": {
+        "name": "trasport1",
+        "description": "Transport Info 1",
+        "type": "REST_HTTP",
+        "protocol": "HTTP",
+        "version": "2",
+        "security": {
+            "grantTypes": "OAUTH2_CLIENT_CREDENTIALS",
+            "tokenEndpoint": "https://token-endpoint/"
+        }
+    }
+  
+    where organization is "etsi:mec" and field name "capifext:transport-info"
+    ```
+
+- Discover API:
+    - On Discover request **SupportedFeatures** is read and checked whether VendSpecQueryParams feature is enabled.
+    - When VendSpecQueryParams is enabled, vendor-specific query parameters are parsed
+    - Vendor specific query parameters are added on the GET request according to the following format:
+    ```
+    https://{{CAPIF_HOSTNAME}}:{{CAPIF_PORT}}/{{DISCOVER_URL}}?
+           ...
+           vend-spec-<query parameter name>={
+              "target": <string that contains the JSON pointer to the attribute in the resource representation>, 
+              "value": <query parameter value>
+    }
+  
+    e.g. 
+    https://{{CAPIF_HOSTNAME}}:{{CAPIF_PORT}}/{{DISCOVER_URL}}?
+           ...
+           vend-spec-type={
+              "target": "/vendorSpecific-urn:etsi:mec:capifext:transport-info", 
+              "value": "REST_HTTP"
+    }
+    ```
+
 #### **Api Status feature**
 
 - Events API:
     - Event internal notifications between services improved to accomplish specification.
-    - On event subscription **SupportedFeatures** is readed and stored in db to accomplish specification.
+    - On event subscription **SupportedFeatures** is read and stored in db to accomplish specification.
     - Also **SupportedFeatures** is checked before send event notification, in order to accomplish specification, sending **eventDetails** and related information according to ***enhanced_event_report*** and ***apiStatusMonitoring*** supported features activated.
 
 #### **Issues**