diff --git a/eval_protocol/pytest/evaluation_test.py b/eval_protocol/pytest/evaluation_test.py
index 5ebd0dfa..8a468843 100644
--- a/eval_protocol/pytest/evaluation_test.py
+++ b/eval_protocol/pytest/evaluation_test.py
@@ -52,10 +52,12 @@
     add_cost_metrics,
     log_eval_status_and_rows,
     parse_ep_completion_params,
+    parse_ep_completion_params_overwrite,
     parse_ep_max_concurrent_rollouts,
     parse_ep_max_rows,
     parse_ep_num_runs,
     parse_ep_passed_threshold,
+    parse_ep_dataloaders,
     rollout_processor_with_retry,
     run_tasks_with_eval_progress,
     run_tasks_with_run_progress,
@@ -189,10 +191,18 @@ def evaluation_test(
     max_concurrent_rollouts = parse_ep_max_concurrent_rollouts(max_concurrent_rollouts)
     max_dataset_rows = parse_ep_max_rows(max_dataset_rows)
     completion_params = parse_ep_completion_params(completion_params)
+    completion_params = parse_ep_completion_params_overwrite(completion_params)
     original_completion_params = completion_params
     passed_threshold = parse_ep_passed_threshold(passed_threshold)
+    data_loaders = parse_ep_dataloaders(data_loaders)
     custom_invocation_id = os.environ.get("EP_INVOCATION_ID", None)
 
+    # ignore other data input params when dataloader is provided
+    if data_loaders:
+        input_dataset = None
+        input_messages = None
+        input_rows = None
+
     def decorator(
         test_func: TestFunction,
     ) -> TestFunction:
diff --git a/eval_protocol/pytest/plugin.py b/eval_protocol/pytest/plugin.py
index 8d369e70..030c367e 100644
--- a/eval_protocol/pytest/plugin.py
+++ b/eval_protocol/pytest/plugin.py
@@ -19,6 +19,7 @@
 import pathlib
 import sys
 from pytest import StashKey
+import pytest
 
 
 def pytest_addoption(parser) -> None:
@@ -56,6 +57,7 @@ def pytest_addoption(parser) -> None:
         default=None,
         help=("Write a JSON summary artifact at the given path (e.g., ./outputs/aime_low.json)."),
     )
+    # deprecate this later
     group.addoption(
         "--ep-input-param",
         action="append",
@@ -115,6 +117,22 @@ def pytest_addoption(parser) -> None:
             "Default: false (experiment JSONs are saved and uploaded by default)."
         ),
     )
+    group.addoption(
+        "--ep-jsonl-path",
+        default=None,
+        help=("Load input from a jsonl file that is already in EvaluationRow or openai CHAT format"),
+    )
+    group.addoption(
+        "--ep-completion-params",
+        default=[],
+        action="append",
+        help=("Overwrite completion params with json. Can be used multiple times. "),
+    )
+    group.addoption(
+        "--ep-remote-rollout-processor-base-url",
+        default=None,
+        help=("If set, use this base URL for remote rollout processing. Example: http://localhost:8000"),
+    )
 
 
 def _normalize_max_rows(val: Optional[str]) -> Optional[str]:
@@ -243,6 +261,15 @@ def pytest_configure(config) -> None:
     if config.getoption("--ep-no-upload"):
         os.environ["EP_NO_UPLOAD"] = "1"
 
+    if config.getoption("--ep-jsonl-path"):
+        os.environ["EP_JSONL_PATH"] = config.getoption("--ep-jsonl-path")
+
+    if config.getoption("--ep-completion-params"):
+        # redump to json to make sure they are legit
+        os.environ["EP_COMPLETION_PARAMS"] = json.dumps(
+            [json.loads(s) for s in config.getoption("--ep-completion-params") or []]
+        )
+
     # Allow ad-hoc overrides of input params via CLI flags
     try:
         merged: dict = {}
diff --git a/eval_protocol/pytest/remote_rollout_processor.py b/eval_protocol/pytest/remote_rollout_processor.py
index 7201e688..bd5c7cef 100644
--- a/eval_protocol/pytest/remote_rollout_processor.py
+++ b/eval_protocol/pytest/remote_rollout_processor.py
@@ -9,6 +9,7 @@
 from eval_protocol.types.remote_rollout_processor import InitRequest, RolloutMetadata
 from .rollout_processor import RolloutProcessor
 from .types import RolloutProcessorConfig
+import os
 
 
 class RemoteRolloutProcessor(RolloutProcessor):
@@ -30,7 +31,8 @@ def __init__(
         # Prefer constructor-provided configuration. These can be overridden via
         # config.kwargs at call time for backward compatibility.
         self._remote_base_url = remote_base_url
-        self._model_base_url = model_base_url
+        if os.getenv("EP_REMOTE_ROLLOUT_PROCESSOR_BASE_URL"):
+            self._remote_base_url = os.getenv("EP_REMOTE_ROLLOUT_PROCESSOR_BASE_URL")
         self._poll_interval = poll_interval
         self._timeout_seconds = timeout_seconds
         self._output_data_loader = output_data_loader
diff --git a/eval_protocol/pytest/utils.py b/eval_protocol/pytest/utils.py
index 4ac472ef..557f5be2 100644
--- a/eval_protocol/pytest/utils.py
+++ b/eval_protocol/pytest/utils.py
@@ -19,6 +19,8 @@
     EvaluationThresholdDict,
     Status,
 )
+from eval_protocol.data_loader import DynamicDataLoader
+from eval_protocol.data_loader.models import EvaluationDataLoader
 from eval_protocol.pytest.rollout_processor import RolloutProcessor
 from eval_protocol.pytest.types import (
     RolloutProcessorConfig,
@@ -239,6 +241,45 @@ def parse_ep_completion_params(
     return completion_params
 
 
+def parse_ep_completion_params_overwrite(
+    completion_params: Sequence[CompletionParams | None] | None,
+) -> Sequence[CompletionParams | None]:
+    new_completion_params = os.getenv("EP_COMPLETION_PARAMS")
+    if new_completion_params:
+        try:
+            new_completion_params_list = json.loads(new_completion_params)
+            if isinstance(new_completion_params_list, list):
+                return new_completion_params_list
+        except Exception:
+            pass
+    return completion_params or []
+
+
+def _rows_from_jsonl(path: str) -> list[EvaluationRow]:
+    rows = []
+    try:
+        with open(path, "r", encoding="utf-8") as f:
+            for line in f:
+                rows.append(EvaluationRow(**json.loads(line)))
+    except Exception as e:
+        print(f"❌ Failed to load rows from JSONL at {path}: {e}")
+        return []
+
+    return rows
+
+
+def parse_ep_dataloaders(
+    dataloaders: Sequence[EvaluationDataLoader] | EvaluationDataLoader | None,
+) -> Sequence[EvaluationDataLoader] | EvaluationDataLoader | None:
+    try:
+        load_from_jsonl_path = os.getenv("EP_JSONL_PATH")
+        if load_from_jsonl_path:
+            return DynamicDataLoader(generators=[lambda path=load_from_jsonl_path: _rows_from_jsonl(path)])
+    except Exception:
+        pass
+    return dataloaders or None
+
+
 def parse_ep_passed_threshold(
     default_value: float | EvaluationThresholdDict | EvaluationThreshold | None,
 ) -> EvaluationThreshold | None:
diff --git a/tests/pytest/test_pytest_env_overwrite.py b/tests/pytest/test_pytest_env_overwrite.py
index c88dd2b8..b4101c72 100644
--- a/tests/pytest/test_pytest_env_overwrite.py
+++ b/tests/pytest/test_pytest_env_overwrite.py
@@ -1,3 +1,6 @@
+import atexit
+import shutil
+import tempfile
 from eval_protocol.models import EvaluationRow, Message
 from eval_protocol.pytest import evaluation_test
 from eval_protocol.pytest.default_no_op_rollout_processor import NoOpRolloutProcessor
@@ -18,3 +21,40 @@ def test_input_messages_in_decorator(row: EvaluationRow) -> EvaluationRow:
         assert row.messages[0].content == "What is the capital of France?"
         assert row.execution_metadata.invocation_id == "test-invocation-123"
         return row
+
+
+with mock.patch.dict(os.environ, {"EP_COMPLETION_PARAMS": '[{"model": "gpt-40"}]'}):
+
+    @evaluation_test(
+        input_rows=[[EvaluationRow(messages=[Message(role="user", content="What is 5 * 6?")])]],
+        completion_params=[{"model": "no-op"}],  # This should be overridden by the env var
+        rollout_processor=NoOpRolloutProcessor(),
+        mode="pointwise",
+    )
+    def test_input_messages_in_env(row: EvaluationRow) -> EvaluationRow:
+        """Run math evaluation on sample dataset using pytest interface."""
+        assert row.messages[0].content == "What is 5 * 6?"
+        assert row.input_metadata.completion_params["model"] == "gpt-40"
+        return row
+
+
+_jsonl_tmpdir = tempfile.mkdtemp()
+atexit.register(shutil.rmtree, _jsonl_tmpdir, ignore_errors=True)
+
+input_path = os.path.join(_jsonl_tmpdir, "input.jsonl")
+with open(input_path, "w") as f:
+    f.write(
+        '{"messages": [{"role": "user", "content": "What is 10 / 2?"}], "input_metadata": {"some_key": "some_value"}}\n'
+    )
+print(f"finish prepare input file {input_path}")
+with mock.patch.dict(os.environ, {"EP_JSONL_PATH": input_path}):
+
+    @evaluation_test(
+        input_rows=[[EvaluationRow(messages=[Message(role="user", content="This will be ignored")])]],
+        completion_params=[{"model": "no-op"}],
+        rollout_processor=NoOpRolloutProcessor(),
+        mode="pointwise",
+    )
+    def test_input_override(row: EvaluationRow) -> EvaluationRow:
+        assert row.messages[0].content == "What is 10 / 2?"
+        return row