test(hello_seller): add smoke coverage for four new rc.1+ stub methods

Add dispatch-path smoke tests for get_media_buys, list_creative_formats,
list_creatives, and provide_performance_feedback, plus a validate_platform
assertion that HelloSeller passes with zero soft-warns. Addresses pre-PR
code-reviewer finding: zero coverage for the new stubs left regression
paths silent. Also align class docstring to say 'soft-required' consistently
with the module docstring and section comment.

https://claude.ai/code/session_01SQEG3PCARK4eKHBbqu4fTS

Author: claude

examples/hello_seller.py

@@ -88,9 +88,10 @@ class HelloSeller(DecisioningPlatform):
     Implements all nine required methods of ``sales-non-guaranteed``: the
     five hard-required (``get_products``, ``create_media_buy``,
     ``update_media_buy``, ``sync_creatives``, ``get_media_buy_delivery``)
-    and the four required by the SalesPlatform Protocol in v6.0 rc.1+
+    and the four soft-required by the SalesPlatform Protocol in v6.0 rc.1+
     (``get_media_buys``, ``list_creative_formats``, ``list_creatives``,
-    ``provide_performance_feedback``).
+    ``provide_performance_feedback``;
+    see :data:`~adcp.decisioning.dispatch.RECOMMENDED_METHODS_PER_SPECIALISM`).
 
     ``validate_platform`` runs at boot and fails fast on any missing
     hard-required method; it soft-warns (or hard-fails in strict mode) for

tests/test_hello_seller_integration.py

@@ -256,3 +256,81 @@ async def test_advertised_tools_class_attribute_set(
     assert "update_media_buy" in PlatformHandler.advertised_tools
     assert "sync_creatives" in PlatformHandler.advertised_tools
     assert "get_media_buy_delivery" in PlatformHandler.advertised_tools
+
+
+@pytest.mark.asyncio
+async def test_get_media_buys_returns_empty_list(handler: PlatformHandler) -> None:
+    """Smoke: stub returns valid wire shape for get_media_buys."""
+    from adcp.types import GetMediaBuysRequest
+
+    req = GetMediaBuysRequest(account={"account_id": "buyer-1"})
+    resp = await handler.get_media_buys(req, ToolContext())
+    assert isinstance(resp, dict)
+    assert resp["media_buys"] == []
+
+
+@pytest.mark.asyncio
+async def test_list_creative_formats_returns_empty_list(handler: PlatformHandler) -> None:
+    """Smoke: stub returns valid wire shape for list_creative_formats."""
+    from adcp.types import ListCreativeFormatsRequest
+
+    req = ListCreativeFormatsRequest()
+    resp = await handler.list_creative_formats(req, ToolContext())
+    assert isinstance(resp, dict)
+    assert resp["formats"] == []
+
+
+@pytest.mark.asyncio
+async def test_list_creatives_returns_empty_list(handler: PlatformHandler) -> None:
+    """Smoke: stub returns valid wire shape for list_creatives."""
+    from adcp.types import ListCreativesRequest
+
+    req = ListCreativesRequest(account={"account_id": "buyer-1"})
+    resp = await handler.list_creatives(req, ToolContext())
+    assert isinstance(resp, dict)
+    assert resp["creatives"] == []
+
+
+@pytest.mark.asyncio
+async def test_provide_performance_feedback_acknowledges(handler: PlatformHandler) -> None:
+    """Smoke: stub returns success acknowledgment for provide_performance_feedback."""
+    from adcp.types import ProvidePerformanceFeedbackRequest
+
+    req = ProvidePerformanceFeedbackRequest(
+        account={"account_id": "buyer-1"},
+        media_buy_id="mb_test",
+        idempotency_key="perf-feedback-test-key-001",
+        measurement_period={"start": "2026-05-01T00:00:00Z", "end": "2026-05-31T23:59:59Z"},
+        performance_index=1.0,
+        feedback=[],
+    )
+    resp = await handler.provide_performance_feedback(req, ToolContext())
+    assert isinstance(resp, dict)
+    assert resp["success"] is True
+
+
+@pytest.mark.asyncio
+async def test_validate_platform_no_soft_warns_on_hello_seller() -> None:
+    """HelloSeller passes validate_platform without any soft-warn for the
+    four RECOMMENDED_METHODS_PER_SPECIALISM methods."""
+    import warnings
+
+    from adcp.decisioning.dispatch import validate_platform
+
+    with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter("always")
+        validate_platform(_hello.HelloSeller())
+    soft_warns = [
+        x
+        for x in w
+        if any(
+            m in str(x.message)
+            for m in [
+                "get_media_buys",
+                "list_creative_formats",
+                "list_creatives",
+                "provide_performance_feedback",
+            ]
+        )
+    ]
+    assert soft_warns == [], f"Unexpected soft-warns: {[str(x.message) for x in soft_warns]}"