Python: Port to Pydantic BaseModel for Durable State

python/packages/azurefunctions/agent_framework_azurefunctions/_constants.py

@@ -1,6 +1,12 @@
 # Copyright (c) Microsoft. All rights reserved.
 
-"""Constants for Azure Functions Agent Framework integration."""
+"""Constants for Azure Functions Agent Framework integration.
+
+This module contains runtime configuration constants (polling, MIME types, headers)
+and API response field names.
+"""
+
+from typing import Final
 
 # Supported request/response formats and MIME types
 REQUEST_RESPONSE_FORMAT_JSON: str = "json"
@@ -17,3 +23,15 @@
 # Polling configuration
 DEFAULT_MAX_POLL_RETRIES: int = 30
 DEFAULT_POLL_INTERVAL_SECONDS: float = 1.0
+
+
+class ApiResponseFields:
+    """Field names for HTTP API responses (not part of persisted schema).
+
+    These are used in try_get_agent_response() for backward compatibility
+    with the HTTP API response format.
+    """
+
+    CONTENT: Final[str] = "content"
+    MESSAGE_COUNT: Final[str] = "message_count"
+    CORRELATION_ID: Final[str] = "correlationId"