diff --git a/conjurer_librarian/conjurer_librarian.py b/conjurer_librarian/conjurer_librarian.py
index 0b2c666..7dc7f79 100644
--- a/conjurer_librarian/conjurer_librarian.py
+++ b/conjurer_librarian/conjurer_librarian.py
@@ -212,6 +212,9 @@ class Librarian(object):
         - search_result_from_cr: A dictionary to store the search results from Crossref.
         - done: A flag indicating if the search is done.
         """
+        # Crossref only needs a contact mailto. It can come from
+        # CONJURER_CROSSREF_MAILTO (the usual container setup) OR from a
+        # "crossref" entry in the netrc; netrc takes precedence when present.
         mailto_contact: Optional[str] = os.getenv("CONJURER_CROSSREF_MAILTO")
         if netrc:
             try:
@@ -219,10 +222,22 @@ class Librarian(object):
                 auth_tokens = netrc_mod.authenticators("crossref")
                 if auth_tokens:
                     mailto_contact = auth_tokens[0]
-            except (FileNotFoundError, netrc.NetrcParseError):
-                logging.getLogger("conjurer_librarian").warning(
-                    "Crossref credentials missing in netrc %s", NETRC_FILE
-                )
+            except (FileNotFoundError, netrc.NetrcParseError) as exc:
+                # A missing/unreadable netrc is NORMAL when the mailto is set via
+                # env - don't cry wolf on every single search. Only warn when we
+                # genuinely have no contact from either source.
+                _log = logging.getLogger("conjurer_librarian")
+                if mailto_contact:
+                    _log.debug(
+                        "netrc %s not used (%s) - using CONJURER_CROSSREF_MAILTO",
+                        NETRC_FILE, exc,
+                    )
+                else:
+                    _log.warning(
+                        "Crossref contact not configured: netrc %s unreadable (%s) "
+                        "and CONJURER_CROSSREF_MAILTO unset",
+                        NETRC_FILE, exc,
+                    )
         if not mailto_contact:
             raise RuntimeError(
                 "Crossref credentials not configured. Set CONJURER_CROSSREF_MAILTO or add to netrc."
diff --git a/tests/integration/test_librarian_crossref_config.py b/tests/integration/test_librarian_crossref_config.py
new file mode 100644
index 0000000..cc588f8
--- /dev/null
+++ b/tests/integration/test_librarian_crossref_config.py
@@ -0,0 +1,52 @@
+"""Integration: the librarian's Crossref-contact resolution.
+
+CONJURER_CROSSREF_MAILTO alone is a valid, complete configuration. A missing
+netrc must NOT produce a "credentials missing" warning in that case - the old
+code warned on every single search even though the env var was set and used.
+Only a genuine absence of any contact should warn (and then raise).
+"""
+import logging
+import sys
+import types
+
+import pytest
+
+if "habanero" not in sys.modules:
+    _habanero = types.ModuleType("habanero")
+    _habanero.Crossref = object
+    sys.modules["habanero"] = _habanero
+
+import conjurer_librarian as lib  # noqa: E402
+
+
+class _DummyCrossref:
+    """Accepts the kwargs the real Crossref does, so Librarian() can construct."""
+
+    def __init__(self, **kwargs):
+        self.kwargs = kwargs
+
+
+@pytest.fixture(autouse=True)
+def _crossref_and_missing_netrc(monkeypatch):
+    # Build with a harmless Crossref, and force the netrc read to miss so the
+    # env-var path is what's exercised.
+    monkeypatch.setattr(lib, "Crossref", _DummyCrossref)
+    monkeypatch.setattr(lib, "NETRC_FILE", "/nonexistent/conjurer/.netrc")
+
+
+def test_env_mailto_alone_does_not_warn(monkeypatch, caplog):
+    monkeypatch.setenv("CONJURER_CROSSREF_MAILTO", "mtuszowski@example.com")
+    with caplog.at_level(logging.WARNING, logger="conjurer_librarian"):
+        librarian = lib.Librarian(lib.app, "kwas foliowy", "uuid-1", False)
+    assert librarian.uuid == "uuid-1"  # constructed fine
+    assert not any(
+        "credentials missing" in r.getMessage().lower()
+        or "not configured" in r.getMessage().lower()
+        for r in caplog.records
+    ), "a missing netrc must not warn when CONJURER_CROSSREF_MAILTO is set"
+
+
+def test_no_contact_anywhere_raises(monkeypatch):
+    monkeypatch.delenv("CONJURER_CROSSREF_MAILTO", raising=False)
+    with pytest.raises(RuntimeError):
+        lib.Librarian(lib.app, "kwas foliowy", "uuid-2", False)