fix: resolve document timestamp type at runtime

airbyte/documents.py

@@ -10,15 +10,12 @@
 
 from __future__ import annotations
 
-from typing import TYPE_CHECKING, Any
+import datetime  # noqa: TC003  # Pydantic resolves this annotation at runtime.
+from typing import Any
 
 from pydantic import BaseModel, Field
 
 
-if TYPE_CHECKING:
-    import datetime
-
-
 MAX_SINGLE_LINE_LENGTH = 60
 AIRBYTE_DOCUMENT_RENDERING = "airbyte_document_rendering"
 TITLE_PROPERTY = "title_property"

tests/unit_tests/test_documents.py

@@ -0,0 +1,49 @@
+# Copyright (c) 2026 Airbyte, Inc., all rights reserved.
+"""Regression coverage for document model construction and rendering."""
+
+from __future__ import annotations
+
+from datetime import datetime as DateTime
+from typing import Any
+
+import pytest
+
+from airbyte._util.document_rendering import DocumentRenderer
+from airbyte.documents import Document
+
+
+@pytest.mark.parametrize(
+    "fields",
+    [
+        {},
+        {"last_modified": None},
+        {"last_modified": "2026-10-20T12:00:00Z"},
+    ],
+)
+def test_document_construction(fields: dict[str, Any]) -> None:
+    """Documents validate without callers rebuilding the model's forward references."""
+    document = Document(content="Example", metadata={"source": "test"}, **fields)
+    assert document.page_content == "Example"
+    assert document.metadata == {"source": "test"}
+    if fields.get("last_modified"):
+        assert document.last_modified == DateTime.fromisoformat(
+            "2026-10-20T12:00:00+00:00"
+        )
+    else:
+        assert document.last_modified is None
+
+
+def test_document_rendering() -> None:
+    """The record-to-document path constructs the document model successfully."""
+    renderer = DocumentRenderer(content_properties=["body"], metadata_properties=["id"])
+    document = renderer.render_document({"body": "Example", "id": "record-1"})
+    assert document.page_content == "Example"
+    assert document.metadata == {"id": "record-1"}
+
+
+def test_document_schema() -> None:
+    """The model's JSON schema resolves the optional timestamp at runtime."""
+    schema = Document.model_json_schema()
+    assert {"type": "string", "format": "date-time"} in schema["properties"][
+        "last_modified"
+    ]["anyOf"]