diff --git a/agent/secret_sources/onepassword.py b/agent/secret_sources/onepassword.py
index 37369a4031..d5ad85659f 100644
--- a/agent/secret_sources/onepassword.py
+++ b/agent/secret_sources/onepassword.py
@@ -38,7 +38,7 @@ _DEFAULT_TOKEN_ENV = "OP_SERVICE_ACCOUNT_TOKEN"
 # dynamically in _op_child_env().
 _OP_ENV_ALLOWLIST = (
     "PATH", "HOME", "USERPROFILE", "APPDATA", "LOCALAPPDATA", "SystemRoot",
-    "TMPDIR", "TMP", "TEMP", "XDG_CONFIG_HOME", "XDG_RUNTIME_DIR",
+    "TMPDIR", "TMP", "TEMP", "XDG_CONFIG_HOME", "XDG_RUNTIME_DIR", "OP_CONFIG_DIR",
     "OP_ACCOUNT", "OP_CONNECT_HOST", "OP_CONNECT_TOKEN",
     # Lets a user skip op's desktop-app integration probe (which can hang with
     # no timeout on a wedged desktop container) and go straight to token auth.
diff --git a/tests/agent/test_onepassword_secrets.py b/tests/agent/test_onepassword_secrets.py
index cafcf60ad3..1f81767542 100644
--- a/tests/agent/test_onepassword_secrets.py
+++ b/tests/agent/test_onepassword_secrets.py
@@ -217,6 +217,17 @@ def test_find_op_pinned_path_not_on_path(tmp_path, monkeypatch):
 
 
 
+def test_op_child_env_forwards_config_directory(monkeypatch):
+    """The op child must retain an explicit 1Password config location."""
+    monkeypatch.setenv("OP_CONFIG_DIR", "/tmp/op-config")
+    monkeypatch.setenv("UNRELATED_PROVIDER_TOKEN", "must-not-leak")
+
+    env = op._op_child_env("")
+
+    assert env["OP_CONFIG_DIR"] == "/tmp/op-config"
+    assert "UNRELATED_PROVIDER_TOKEN" not in env
+
+
 # ---------------------------------------------------------------------------
 # apply_onepassword_secrets
 # ---------------------------------------------------------------------------
diff --git a/tests/agent/test_vault_backends.py b/tests/agent/test_vault_backends.py
index 74c06cad07..60898cbecf 100644
--- a/tests/agent/test_vault_backends.py
+++ b/tests/agent/test_vault_backends.py
@@ -221,3 +221,13 @@ def test_onepassword_multi_url_item_binds_every_saved_web_origin():
     # helpers: dedupe keeps first occurrence; app-only items keep their single origin
     assert _all_origins(["https://a.com/x", "https://a.com/y"]) == ["https://a.com"]
     assert _web_origins(["androidapp://com.x"]) == ("androidapp://com.x",)
+
+
+def test_onepassword_backend_env_forwards_config_directory(monkeypatch):
+    """Vault reads use the same explicit 1Password CLI config location."""
+    from agent.vault_backends.onepassword import OnePasswordLoginBackend
+
+    monkeypatch.setenv("OP_CONFIG_DIR", "/tmp/op-config")
+    backend = OnePasswordLoginBackend({"enabled": True})
+
+    assert backend._env(None)["OP_CONFIG_DIR"] == "/tmp/op-config"