LCORE-1051: final updates

src/app/endpoints/a2a.py

@@ -5,7 +5,7 @@
 import logging
 import uuid
 from datetime import datetime, timezone
-from typing import Annotated, Any, AsyncIterator, MutableMapping
+from typing import Annotated, Any, AsyncIterator, MutableMapping, Optional
 
 from fastapi import APIRouter, Depends, HTTPException, Request, status
 from llama_stack.apis.agents.openai_responses import (
@@ -65,8 +65,8 @@
 # Task store and context store are created lazily based on configuration.
 # For multi-worker deployments, configure 'a2a_state' with 'sqlite' or 'postgres'
 # to share state across workers.
-_TASK_STORE: TaskStore | None = None
-_CONTEXT_STORE: A2AContextStore | None = None
+_TASK_STORE: Optional[TaskStore] = None
+_CONTEXT_STORE: Optional[A2AContextStore] = None
 
 
 async def _get_task_store() -> TaskStore:
@@ -120,7 +120,7 @@ class TaskResultAggregator:
     def __init__(self) -> None:
         """Initialize the task result aggregator with default state."""
         self._task_state: TaskState = TaskState.working
-        self._task_status_message: Message | None = None
+        self._task_status_message: Optional[Message] = None
 
     def process_event(
         self, event: TaskStatusUpdateEvent | TaskArtifactUpdateEvent | Any
@@ -169,7 +169,7 @@ def task_state(self) -> TaskState:
         return self._task_state
 
     @property
-    def task_status_message(self) -> Message | None:
+    def task_status_message(self) -> Optional[Message]:
         """Return the current task status message."""
         return self._task_status_message
 
@@ -185,7 +185,7 @@ class A2AAgentExecutor(AgentExecutor):
     """
 
     def __init__(
-        self, auth_token: str, mcp_headers: dict[str, dict[str, str]] | None = None
+        self, auth_token: str, mcp_headers: Optional[dict[str, dict[str, str]]] = None
     ):
         """Initialize the A2A agent executor.
 
@@ -413,7 +413,7 @@ async def _convert_stream_to_events(  # pylint: disable=too-many-branches,too-ma
         stream: AsyncIterator[OpenAIResponseObjectStream],
         task_id: str,
         context_id: str,
-        conversation_id: str | None,
+        conversation_id: Optional[str],
     ) -> AsyncIterator[Any]:
         """Convert Responses API stream chunks to A2A events.
 

src/app/endpoints/query.py

@@ -156,12 +156,12 @@ def persist_user_conversation_details(
 
 
 def evaluate_model_hints(
-    user_conversation: UserConversation | None,
+    user_conversation: Optional[UserConversation],
     query_request: QueryRequest,
-) -> tuple[str | None, str | None]:
+) -> tuple[Optional[str], Optional[str]]:
     """Evaluate model hints from user conversation."""
-    model_id: str | None = query_request.model
-    provider_id: str | None = query_request.provider
+    model_id: Optional[str] = query_request.model
+    provider_id: Optional[str] = query_request.provider
 
     if user_conversation is not None:
         if query_request.model is not None:
@@ -271,7 +271,7 @@ async def query_endpoint_handler_base(  # pylint: disable=R0914
     user_id, _, _skip_userid_check, token = auth
 
     started_at = datetime.now(UTC).strftime("%Y-%m-%dT%H:%M:%SZ")
-    user_conversation: UserConversation | None = None
+    user_conversation: Optional[UserConversation] = None
     if query_request.conversation_id:
         logger.debug(
             "Conversation ID specified in query: %s", query_request.conversation_id
@@ -483,7 +483,7 @@ async def query_endpoint_handler(
 
 
 def select_model_and_provider_id(
-    models: ModelListResponse, model_id: str | None, provider_id: str | None
+    models: ModelListResponse, model_id: Optional[str], provider_id: Optional[str]
 ) -> tuple[str, str, str]:
     """
     Select the model ID and provider ID based on the request or available models.
@@ -663,7 +663,7 @@ async def retrieve_response(  # pylint: disable=too-many-locals,too-many-branche
     model_id: str,
     query_request: QueryRequest,
     token: str,
-    mcp_headers: dict[str, dict[str, str]] | None = None,
+    mcp_headers: Optional[dict[str, dict[str, str]]] = None,
     *,
     provider_id: str = "",
 ) -> tuple[TurnSummary, str, list[ReferencedDocument], TokenCounter]:
@@ -859,7 +859,7 @@ def validate_attachments_metadata(attachments: list[Attachment]) -> None:
 
 def get_rag_toolgroups(
     vector_db_ids: list[str],
-) -> list[Toolgroup] | None:
+) -> Optional[list[Toolgroup]]:
     """
     Return a list of RAG Tool groups if the given vector DB list is not empty.
 
@@ -870,7 +870,7 @@ def get_rag_toolgroups(
         vector_db_ids (list[str]): List of vector database identifiers to include in the toolgroup.
 
     Returns:
-        list[Toolgroup] | None: A list with a single RAG toolgroup if
+        Optional[list[Toolgroup]]: A list with a single RAG toolgroup if
         vector_db_ids is non-empty; otherwise, None.
     """
     return (

src/app/endpoints/query_v2.py

@@ -4,7 +4,7 @@
 
 import json
 import logging
-from typing import Annotated, Any, cast
+from typing import Annotated, Any, Optional, cast
 
 from fastapi import APIRouter, Depends, Request
 from llama_stack.apis.agents.openai_responses import (
@@ -74,7 +74,7 @@
 
 def _build_tool_call_summary(  # pylint: disable=too-many-return-statements,too-many-branches
     output_item: Any,
-) -> tuple[ToolCallSummary | None, ToolResultSummary | None]:
+) -> tuple[Optional[ToolCallSummary], Optional[ToolResultSummary]]:
     """Translate applicable Responses API tool outputs into ``ToolCallSummary`` records.
 
     The OpenAI ``response.output`` array may contain any ``OpenAIResponseOutput`` variant:
@@ -110,7 +110,7 @@ def _build_tool_call_summary(  # pylint: disable=too-many-return-statements,too-
             "status": getattr(output_item, "status", None),
         }
         results = getattr(output_item, "results", None)
-        response_payload: Any | None = None
+        response_payload: Optional[Any] = None
         if results is not None:
             # Store only the essential result metadata to avoid large payloads
             response_payload = {
@@ -294,7 +294,7 @@ async def retrieve_response(  # pylint: disable=too-many-locals,too-many-branche
     model_id: str,
     query_request: QueryRequest,
     token: str,
-    mcp_headers: dict[str, dict[str, str]] | None = None,
+    mcp_headers: Optional[dict[str, dict[str, str]]] = None,
     *,
     provider_id: str = "",
 ) -> tuple[TurnSummary, str, list[ReferencedDocument], TokenCounter]:
@@ -505,7 +505,7 @@ def parse_referenced_documents_from_responses_api(
     """
     documents: list[ReferencedDocument] = []
     # Use a set to track unique documents by (doc_url, doc_title) tuple
-    seen_docs: set[tuple[str | None, str | None]] = set()
+    seen_docs: set[tuple[Optional[str], Optional[str]]] = set()
 
     if not response.output:
         return documents
@@ -535,7 +535,7 @@ def parse_referenced_documents_from_responses_api(
 
                 # If we have at least a filename or url
                 if filename or doc_url:
-                    # Treat empty string as None for URL to satisfy AnyUrl | None
+                    # Treat empty string as None for URL to satisfy Optional[AnyUrl]
                     final_url = doc_url if doc_url else None
                     if (final_url, filename) not in seen_docs:
                         documents.append(
@@ -692,15 +692,15 @@ def _increment_llm_call_metric(provider: str, model: str) -> None:
         logger.warning("Failed to update LLM call metric: %s", e)
 
 
-def get_rag_tools(vector_store_ids: list[str]) -> list[dict[str, Any]] | None:
+def get_rag_tools(vector_store_ids: list[str]) -> Optional[list[dict[str, Any]]]:
     """
     Convert vector store IDs to tools format for Responses API.
 
     Args:
         vector_store_ids: List of vector store identifiers
 
     Returns:
-        list[dict[str, Any]] | None: List containing file_search tool configuration,
+        Optional[list[dict[str, Any]]]: List containing file_search tool configuration,
         or None if no vector stores provided
     """
     if not vector_store_ids:
@@ -717,8 +717,8 @@ def get_rag_tools(vector_store_ids: list[str]) -> list[dict[str, Any]] | None:
 
 def get_mcp_tools(
     mcp_servers: list,
-    token: str | None = None,
-    mcp_headers: dict[str, dict[str, str]] | None = None,
+    token: Optional[str] = None,
+    mcp_headers: Optional[dict[str, dict[str, str]]] = None,
 ) -> list[dict[str, Any]]:
     """
     Convert MCP servers to tools format for Responses API.
@@ -762,8 +762,8 @@ async def prepare_tools_for_responses_api(
     query_request: QueryRequest,
     token: str,
     config: AppConfig,
-    mcp_headers: dict[str, dict[str, str]] | None = None,
-) -> list[dict[str, Any]] | None:
+    mcp_headers: Optional[dict[str, dict[str, str]]] = None,
+) -> Optional[list[dict[str, Any]]]:
     """
     Prepare tools for Responses API including RAG and MCP tools.
 
@@ -778,7 +778,7 @@ async def prepare_tools_for_responses_api(
         mcp_headers: Per-request headers for MCP servers
 
     Returns:
-        list[dict[str, Any]] | None: List of tool configurations for the
+        Optional[list[dict[str, Any]]]: List of tool configurations for the
         Responses API, or None if no_tools is True or no tools are available
     """
     if query_request.no_tools:

src/app/endpoints/streaming_query.py

@@ -7,7 +7,15 @@
 import uuid
 from collections.abc import Callable
 from datetime import UTC, datetime
-from typing import Annotated, Any, AsyncGenerator, AsyncIterator, Iterator, cast
+from typing import (
+    Annotated,
+    Any,
+    AsyncGenerator,
+    AsyncIterator,
+    Iterator,
+    Optional,
+    cast,
+)
 
 from fastapi import APIRouter, Depends, Request
 from fastapi.responses import StreamingResponse
@@ -231,7 +239,7 @@ def stream_build_event(
     chunk_id: int,
     metadata_map: dict,
     media_type: str = MEDIA_TYPE_JSON,
-    conversation_id: str | None = None,
+    conversation_id: Optional[str] = None,
 ) -> Iterator[str]:
     """Build a streaming event from a chunk response.
 
@@ -384,7 +392,7 @@ async def stream_http_error(error: AbstractErrorResponse) -> AsyncGenerator[str,
 def _handle_turn_start_event(
     _chunk_id: int,
     media_type: str = MEDIA_TYPE_JSON,
-    conversation_id: str | None = None,
+    conversation_id: Optional[str] = None,
 ) -> Iterator[str]:
     """
     Yield turn start event.
@@ -734,7 +742,7 @@ async def response_generator(
         # Send start event at the beginning of the stream
         yield stream_start_event(context.conversation_id)
 
-        latest_turn: Any | None = None
+        latest_turn: Optional[Any] = None
 
         async for chunk in turn_response:
             if chunk.event is None:
@@ -850,7 +858,7 @@ async def streaming_query_endpoint_handler_base(  # pylint: disable=too-many-loc
 
     user_id, _user_name, _skip_userid_check, token = auth
 
-    user_conversation: UserConversation | None = None
+    user_conversation: Optional[UserConversation] = None
     if query_request.conversation_id:
         user_conversation = validate_conversation_ownership(
             user_id=user_id, conversation_id=query_request.conversation_id
@@ -1001,7 +1009,7 @@ async def retrieve_response(
     model_id: str,
     query_request: QueryRequest,
     token: str,
-    mcp_headers: dict[str, dict[str, str]] | None = None,
+    mcp_headers: Optional[dict[str, dict[str, str]]] = None,
 ) -> tuple[AsyncIterator[AgentTurnResponseStreamChunk], str]:
     """
     Retrieve response from LLMs and agents.

src/app/endpoints/streaming_query_v2.py

@@ -1,7 +1,7 @@
 """Streaming query handler using Responses API (v2)."""
 
 import logging
-from typing import Annotated, Any, AsyncIterator, cast
+from typing import Annotated, Any, AsyncIterator, Optional, cast
 
 from fastapi import APIRouter, Depends, Request
 from fastapi.responses import StreamingResponse
@@ -138,7 +138,7 @@ async def response_generator(  # pylint: disable=too-many-branches,too-many-stat
         start_event_emitted = False
 
         # Track the latest response object from response.completed event
-        latest_response_object: Any | None = None
+        latest_response_object: Optional[Any] = None
 
         logger.debug("Starting streaming response (Responses API) processing")
 
@@ -372,7 +372,7 @@ async def retrieve_response(  # pylint: disable=too-many-locals
     model_id: str,
     query_request: QueryRequest,
     token: str,
-    mcp_headers: dict[str, dict[str, str]] | None = None,
+    mcp_headers: Optional[dict[str, dict[str, str]]] = None,
 ) -> tuple[AsyncIterator[OpenAIResponseObjectStream], str]:
     """
     Retrieve response from LLMs and agents.
@@ -471,7 +471,7 @@ async def retrieve_response(  # pylint: disable=too-many-locals
 
 async def create_violation_stream(
     message: str,
-    shield_model: str | None = None,
+    shield_model: Optional[str] = None,
 ) -> AsyncIterator[OpenAIResponseObjectStream]:
     """Generate a minimal streaming response for cases where input is blocked by a shield.
 

src/utils/types.py

@@ -104,8 +104,8 @@ class ShieldModerationResult(BaseModel):
     """Result of shield moderation check."""
 
     blocked: bool
-    message: str | None = None
-    shield_model: str | None = None
+    message: Optional[str] = None
+    shield_model: Optional[str] = None
 
 
 class ToolCallSummary(BaseModel):