diff --git a/evaluations/evaluations/benchmark.py b/evaluations/evaluations/benchmark.py
index 0f58de66..b24668b1 100644
--- a/evaluations/evaluations/benchmark.py
+++ b/evaluations/evaluations/benchmark.py
@@ -406,6 +406,16 @@ async def run_qa_benchmark(
     skill_factory = _skill_factory_for_target(target)
     resolved_skill_model = get_model(skill_config, config)
 
+    from haiku.rag.tools.filters import build_multi_document_filter
+
+    question_to_filter: dict[str, str | None] = {}
+    for case in cases:
+        meta = case.metadata or {}
+        target_uri = meta.get("target_doc_uri")
+        question_to_filter[case.inputs] = (
+            build_multi_document_filter([target_uri]) if target_uri else None
+        )
+
     async def answer_question(question: str) -> str:
         result = await run_skill_question(
             skill_factory=skill_factory,
@@ -413,6 +423,7 @@ async def run_qa_benchmark(
             config=config,
             question=question,
             skill_model=resolved_skill_model,
+            document_filter=question_to_filter.get(question),
         )
         set_eval_attribute("cited_uris", result.cited_uris)
         return result.answer
diff --git a/evaluations/evaluations/datasets/mmlongbench.py b/evaluations/evaluations/datasets/mmlongbench.py
index 120cba90..436f9e1f 100644
--- a/evaluations/evaluations/datasets/mmlongbench.py
+++ b/evaluations/evaluations/datasets/mmlongbench.py
@@ -105,6 +105,7 @@ def build_mmlb_case(
     metadata: dict[str, str] = {
         "case_index": str(index),
         "doc_id": doc["doc_id"],
+        "target_doc_uri": doc["doc_id"],
         "doc_type": doc.get("doc_type", ""),
         "answer_format": doc.get("answer_format", ""),
         "evidence_pages": str(evidence_pages),
diff --git a/evaluations/tests/test_datasets.py b/evaluations/tests/test_datasets.py
index 82e792c8..66f9a844 100644
--- a/evaluations/tests/test_datasets.py
+++ b/evaluations/tests/test_datasets.py
@@ -240,6 +240,7 @@ class TestMMLongBenchDoc:
         assert case.expected_output == "42"
         assert case.metadata is not None
         assert case.metadata["doc_id"] == "report.pdf"
+        assert case.metadata["target_doc_uri"] == "report.pdf"
         assert case.metadata["doc_type"] == "Financial report"
         assert case.metadata["answer_format"] == "Int"
         assert case.metadata["evidence_pages"] == "[5]"