refactor scoring/eval pytests (#607)

# What does this PR do?

- remove model registration & parameterize model in scoring/eval pytests

## Test Plan

```
pytest -v -s -m meta_reference_eval_together_inference eval/test_eval.py
pytest -v -s -m meta_reference_eval_together_inference_huggingface_datasetio eval/test_eval.py
```

```
pytest -v -s -m llm_as_judge_scoring_together_inference scoring/test_scoring.py --judge-model meta-llama/Llama-3.2-3B-Instruct
pytest -v -s -m basic_scoring_together_inference scoring/test_scoring.py
```
<img width="860" alt="image"
src="https://github.com/user-attachments/assets/d4b0badc-da34-4097-9b7c-9511f8261723"
/>


## Sources

Please link relevant resources if necessary.


## Before submitting

- [ ] This PR fixes a typo or improves the docs (you can dismiss the
other checks if that's the case).
- [ ] Ran pre-commit to handle lint / formatting issues.
- [ ] Read the [contributor
guideline](https://github.com/meta-llama/llama-stack/blob/main/CONTRIBUTING.md),
      Pull Request section?
- [ ] Updated relevant documentation.
- [ ] Wrote necessary unit or integration tests.

llama_stack/providers/tests/scoring/conftest.py

@@ -47,6 +47,7 @@ def pytest_configure(config):
     for fixture_name in [
         "basic_scoring_together_inference",
         "braintrust_scoring_together_inference",
+        "llm_as_judge_scoring_together_inference",
     ]:
         config.addinivalue_line(
             "markers",
@@ -61,9 +62,23 @@ def pytest_addoption(parser):
         default="meta-llama/Llama-3.2-3B-Instruct",
         help="Specify the inference model to use for testing",
     )
+    parser.addoption(
+        "--judge-model",
+        action="store",
+        default="meta-llama/Llama-3.1-8B-Instruct",
+        help="Specify the judge model to use for testing",
+    )
 
 
 def pytest_generate_tests(metafunc):
+    judge_model = metafunc.config.getoption("--judge-model")
+    if "judge_model" in metafunc.fixturenames:
+        metafunc.parametrize(
+            "judge_model",
+            [pytest.param(judge_model, id="")],
+            indirect=True,
+        )
+
     if "scoring_stack" in metafunc.fixturenames:
         available_fixtures = {
             "scoring": SCORING_FIXTURES,

llama_stack/providers/tests/scoring/fixtures.py

@@ -21,6 +21,13 @@ def scoring_remote() -> ProviderFixture:
     return remote_stack_fixture()
 
 
+@pytest.fixture(scope="session")
+def judge_model(request):
+    if hasattr(request, "param"):
+        return request.param
+    return request.config.getoption("--judge-model", None)
+
+
 @pytest.fixture(scope="session")
 def scoring_basic() -> ProviderFixture:
     return ProviderFixture(
@@ -66,7 +73,7 @@ SCORING_FIXTURES = ["basic", "remote", "braintrust", "llm_as_judge"]
 
 
 @pytest_asyncio.fixture(scope="session")
-async def scoring_stack(request, inference_model):
+async def scoring_stack(request, inference_model, judge_model):
     fixture_dict = request.param
 
     providers = {}
@@ -85,8 +92,7 @@ async def scoring_stack(request, inference_model):
             ModelInput(model_id=model)
             for model in [
                 inference_model,
-                "Llama3.1-405B-Instruct",
-                "Llama3.1-8B-Instruct",
+                judge_model,
             ]
         ],
     )

llama_stack/providers/tests/scoring/test_scoring.py

@@ -64,12 +64,6 @@ class TestScoring:
         response = await datasets_impl.list_datasets()
         assert len(response) == 1
 
-        for model_id in ["Llama3.2-3B-Instruct", "Llama3.1-8B-Instruct"]:
-            await models_impl.register_model(
-                model_id=model_id,
-                provider_id="",
-            )
-
         # scoring individual rows
         rows = await datasetio_impl.get_rows_paginated(
             dataset_id="test_dataset",
@@ -103,7 +97,7 @@ class TestScoring:
 
     @pytest.mark.asyncio
     async def test_scoring_score_with_params_llm_as_judge(
-        self, scoring_stack, sample_judge_prompt_template
+        self, scoring_stack, sample_judge_prompt_template, judge_model
     ):
         (
             scoring_impl,
@@ -122,12 +116,6 @@ class TestScoring:
         response = await datasets_impl.list_datasets()
         assert len(response) == 1
 
-        for model_id in ["Llama3.1-405B-Instruct"]:
-            await models_impl.register_model(
-                model_id=model_id,
-                provider_id="",
-            )
-
         scoring_fns_list = await scoring_functions_impl.list_scoring_functions()
         provider_id = scoring_fns_list[0].provider_id
         if provider_id == "braintrust" or provider_id == "basic":
@@ -142,7 +130,7 @@ class TestScoring:
 
         scoring_functions = {
             "llm-as-judge::base": LLMAsJudgeScoringFnParams(
-                judge_model="Llama3.1-405B-Instruct",
+                judge_model=judge_model,
                 prompt_template=sample_judge_prompt_template,
                 judge_score_regexes=[r"Score: (\d+)"],
                 aggregation_functions=[AggregationFunctionType.categorical_count],
@@ -170,7 +158,7 @@ class TestScoring:
 
     @pytest.mark.asyncio
     async def test_scoring_score_with_aggregation_functions(
-        self, scoring_stack, sample_judge_prompt_template
+        self, scoring_stack, sample_judge_prompt_template, judge_model
     ):
         (
             scoring_impl,
@@ -204,7 +192,7 @@ class TestScoring:
             if x.provider_id == "llm-as-judge":
                 aggr_fns = [AggregationFunctionType.categorical_count]
                 scoring_functions[x.identifier] = LLMAsJudgeScoringFnParams(
-                    judge_model="Llama3.1-405B-Instruct",
+                    judge_model=judge_model,
                     prompt_template=sample_judge_prompt_template,
                     judge_score_regexes=[r"Score: (\d+)"],
                     aggregation_functions=aggr_fns,