Address Copilot comments

Author: gabor-openai

src/guardrails/agents.py

@@ -644,7 +644,7 @@ def __new__(
         prompt_arg: Any | None = agent_kwargs.get("prompt")
         resolved_instructions = _resolve_agent_instructions(instructions, prompt_arg)
 
-        if resolved_instructions is None and prompt_arg is None:
+        if resolved_instructions is None:
             raise ValueError(
                 "GuardrailAgent requires either 'instructions' or 'prompt' to initialize the underlying Agent."
             )

tests/conftest.py

@@ -12,6 +12,7 @@
 import types
 from collections.abc import Iterator
 from dataclasses import dataclass
+from pathlib import Path
 from types import SimpleNamespace
 from typing import Any
 
@@ -55,6 +56,11 @@ class _DummyResponse:
     delta: str | None = None
 
 
+_GUARDRAILS_PACKAGE_STUB = types.ModuleType("guardrails")
+_GUARDRAILS_PACKAGE_STUB.__path__ = [str(Path(__file__).resolve().parents[1] / "src" / "guardrails")]
+sys.modules.setdefault("guardrails", _GUARDRAILS_PACKAGE_STUB)
+
+
 _STUB_OPENAI_MODULE = types.ModuleType("openai")
 _STUB_OPENAI_MODULE.AsyncOpenAI = _StubAsyncOpenAI
 _STUB_OPENAI_MODULE.OpenAI = _StubSyncOpenAI

tests/unit/test_agents.py

@@ -6,18 +6,13 @@
 import types
 from collections.abc import Callable
 from dataclasses import dataclass
-from pathlib import Path
 from types import SimpleNamespace
 from typing import Any
 
 import pytest
 
-guardrails_pkg = types.ModuleType("guardrails")
-guardrails_pkg.__path__ = [str(Path(__file__).resolve().parents[2] / "src" / "guardrails")]
-sys.modules.setdefault("guardrails", guardrails_pkg)
-
-from guardrails._openai_utils import SAFETY_IDENTIFIER_HEADER, SAFETY_IDENTIFIER_VALUE  # noqa: E402
-from guardrails.types import GuardrailResult  # noqa: E402
+from guardrails._openai_utils import SAFETY_IDENTIFIER_HEADER, SAFETY_IDENTIFIER_VALUE
+from guardrails.types import GuardrailResult
 
 # ---------------------------------------------------------------------------
 # Stub agents SDK module so guardrails.agents can import required symbols.