doc: update opik integration doc

docs/my-website/docs/observability/opik_integration.md

@@ -140,6 +140,7 @@ These can be passed inside metadata with the `opik` key.
 - `project_name` - Name of the Opik project to send data to.
 - `current_span_data` - The current span data to be used for tracing.
 - `tags` - Tags to be used for tracing.
+- `thread_id` - The thread id to group together multiple related traces.
 
 ### Usage
 
@@ -159,8 +160,10 @@ response = litellm.completion(
     messages=messages,
     metadata = {
         "opik": {
+            "project_name": "your-opik-project-name",
             "current_span_data": get_current_span_data(),
             "tags": ["streaming-test"],
+            "thread_id": "your-thread-id"
         },
     }
 )
@@ -174,7 +177,7 @@ curl -L -X POST 'http://0.0.0.0:4000/v1/chat/completions' \
 -H 'Content-Type: application/json' \
 -H 'Authorization: Bearer sk-1234' \
 -d '{
-  "model": "gpt-3.5-turbo-testing",
+  "model": "gpt-3.5-turbo",
   "messages": [
     {
       "role": "user",
@@ -183,8 +186,10 @@ curl -L -X POST 'http://0.0.0.0:4000/v1/chat/completions' \
   ],
   "metadata": {
     "opik": {
+      "project_name": "your-opik-project-name",
       "current_span_data": "...",
       "tags": ["streaming-test"],
+      "thread_id": "your-thread-id"
     },
   }
 }'
@@ -193,14 +198,25 @@ curl -L -X POST 'http://0.0.0.0:4000/v1/chat/completions' \
 </TabItem>
 </Tabs>
 
+You can also pass the fields as part of the request header with a `opik_*` prefix:
 
-
-
-
-
-
-
-
+```shell
+curl --location --request POST 'http://0.0.0.0:4000/chat/completions' \
+    --header 'Content-Type: application/json' \
+    --header 'Authorization: Bearer sk-1234' \
+    --header 'opik_project_name: your-opik-project-name' \
+    --header 'opik_thread_id: your-thread-id' \
+    --header 'opik_tags: ["streaming-test"]' \
+    --data '{
+    "model": "gpt-3.5-turbo",
+    "messages": [
+        {
+        "role": "user",
+        "content": "What's the weather like in Boston today?"
+        }
+    ]
+}'
+```