[OPIK-5877] create_chat_prompt uses authenticated client instead of global client (#6258)

* [OPIK-5877] fix chat prompt creation

* [OPIK-5877] apply validation

* [OPIK-5877] fix tests

* Trigger pipeline re-run

* Trigger pipeline re-run

* [OPIK-5877] move import

Author: anastasiapyzhik

sdks/python/src/opik/api_objects/opik_client.py

@@ -2,6 +2,7 @@
 import contextvars
 import datetime
 import functools
+import json
 import logging
 from typing import (
     Any,
@@ -45,6 +46,7 @@
 from .experiment import rest_operations as experiment_rest_operations
 from . import prompt as prompt_module
 from .prompt import client as prompt_client
+from ..validation.chat_prompt_messages import ChatPromptMessagesValidator
 from .agent_config.base import Config
 from .agent_config.config import ConfigManager
 from .threads import threads_client
@@ -2069,18 +2071,28 @@ def create_chat_prompt(
             PromptTemplateStructureMismatch: If a text prompt with the same name already exists (template structure is immutable).
             ApiError: If there is an error during the creation of the prompt.
         """
+        validator = ChatPromptMessagesValidator(messages)
+        validator.validate()
+        validator.raise_if_validation_failed()
+
+        prompt_client_ = prompt_client.PromptClient(self._rest_client)
         project_name = self._resolve_project_name(project_name)
-        return prompt_module.ChatPrompt(
+        messages_str = json.dumps(messages)
+        prompt_version = prompt_client_.create_prompt(
             name=name,
-            messages=messages,
+            prompt=messages_str,
             metadata=metadata,
             type=type,
+            template_structure="chat",
             id=id,
             description=description,
             change_description=change_description,
             tags=tags,
             project_name=project_name,
         )
+        return prompt_module.ChatPrompt.from_fern_prompt_version(
+            name, prompt_version, project_name=project_name
+        )
 
     def get_prompt(
         self,

sdks/python/tests/unit/api_objects/test_opik_client.py

@@ -956,8 +956,13 @@ class TestOpikClientCreateChatPrompt:
     def setup(self):
         self.opik_client_ = opik_client.Opik(project_name="default-project")
         self.messages = [{"role": "user", "content": "Hello"}]
+        self.mock_version = _make_chat_prompt_version()
 
-        with patch.object(prompt_module.ChatPrompt, "sync_with_backend"):
+        with patch.object(
+            prompt_client_module.PromptClient,
+            "create_prompt",
+            return_value=self.mock_version,
+        ) as self.mock_create:
             yield
 
     def test_create_chat_prompt__no_project_name__uses_default_project(self):