diff --git a/src/tenantq/search.py b/src/tenantq/search.py
index 41cc5c4..996e9df 100644
--- a/src/tenantq/search.py
+++ b/src/tenantq/search.py
@@ -91,6 +91,8 @@ def search(
     prefetch_limit: int = 50,
 ) -> List[SearchHit]:
     """Run a tenant-isolated search in the requested retrieval mode."""
+    if limit < 1:
+        raise ValueError(f"limit must be >= 1, got {limit!r}")
     qfilter = build_filter(tenant_id, category, created_after, created_before)
     params = models.SearchParams(hnsw_ef=settings.hnsw.hnsw_ef)
 
diff --git a/tests/test_search.py b/tests/test_search.py
index 661e0bc..0da52b0 100644
--- a/tests/test_search.py
+++ b/tests/test_search.py
@@ -38,3 +38,13 @@ def test_created_at_range_filter(ingested, settings, embedder, dataset):
     by_id = {d.id: d for d in dataset.documents}
     for h in hits:
         assert lo <= by_id[h.id].created_at <= hi
+
+
+def test_search_rejects_non_positive_limit(ingested, settings, embedder):
+    import pytest
+    from tenantq.search import search
+
+    with pytest.raises(ValueError, match="limit must be >= 1"):
+        search(ingested, settings, embedder, "query", tenant_id="acme", limit=0)
+    with pytest.raises(ValueError, match="limit must be >= 1"):
+        search(ingested, settings, embedder, "query", tenant_id="acme", limit=-5)