diff --git a/README.md b/README.md
index 5886552..4a5c609 100644
--- a/README.md
+++ b/README.md
@@ -6,17 +6,13 @@ Intelligent resource placement module for 5GCity distributed cloud and radio pla
 
 *The main goal of the algorith is to take into consideration the network topology and the access points locations in determining the best option for placing the VNFs that compose a Network Service.* 
 
-## Configuration
+## Input 
 
-1) Device (Network) graph - a description of the available nodes (data-center, edge) and the interconnections between them
-2) Available resources per device - CPU, Memory, Storage
-3) Connection links capacity
-
-## Input
-
-Network Service (NS) placement request
-- NS description (VNFs, resource requirements)
-- NS user gateway - the end node where the NS user is connected 
+1) Network Service (NS) placement request
+2) Device (Network) graph - a description of the available nodes (data-center, edge) and the interconnections between them
+3) Available resources per device - CPU, Memory, Storage
+4) Connection links capacity
+5) NS user gateway - the end node where the NS user is connected 
 
   *In 5GCity, we can assume that end users of a NS are the SCs and the WiFi APs and the NS gateway is the edge or DC node to which they have a direct connection*
 
@@ -24,6 +20,51 @@ Network Service (NS) placement request
 
 The output of the module is one or a group of devices where the NS should be placed.
 
+## API Usage
+
+### POST Endpoint  http://localhost:3800/placement/
+
+Triggers the placement algorithm. The needed input information is extracted from the slice data (compute and network chunks, resources, links).
+
+- Asynchronous, returns an id of the request.
+- The progress can be checked by GET /placement/{placement-id} and reading the status (READY, IN PROGRESS, FAIL).
+
+#### Body Example 
+```
+{
+   TBD ...
+   "nsd",
+   "slice"
+}
+```
+#### Response 
+
+- {placement-id}: id of the placement request as body
+- Response codes: 202 Accepted,  400 Bad Request
+
+### GET Endpoint http://localhost:3800/placement/{placement-id}
+
+#### Response
+
+Body example
+```
+{    
+    "status: "READY",
+    "ns_id":"6b63089158f568073093f70a",
+    "placemenet-map":[  
+        {  
+            "chunk_id":"6b63089158f568073093f70a",
+            "vdu_id":"6b63089158f568073093f70a"
+        },
+        {  
+            "chunk_id":"6b63089158f568073093p11c",
+            "vdu_id":"6b63089158f568073093f90b"
+        }
+    ]"
+}
+```
+
+Response codes: 200 OK, 404 Item Not Found