diff --git a/tests/test_affiliates/test_integration.py b/tests/test_affiliates/test_integration.py
new file mode 100644
index 0000000..8256367
--- /dev/null
+++ b/tests/test_affiliates/test_integration.py
@@ -0,0 +1,60 @@
+"""Integration tests — full wrap_url() round-trip through public API."""
+import pytest
+from circuitforge_core.affiliates import wrap_url, get_disclosure_text
+
+
+class TestEbayIntegration:
+    def test_full_flow_with_env_var(self, monkeypatch):
+        monkeypatch.setenv("EBAY_AFFILIATE_CAMPAIGN_ID", "cf-snipe-999")
+        url = wrap_url("https://www.ebay.com/itm/987654321", retailer="ebay")
+        assert "campid=cf-snipe-999" in url
+        assert "mkcid=1" in url
+        assert "mkevt=1" in url
+
+    def test_full_flow_with_opt_out(self, monkeypatch):
+        monkeypatch.setenv("EBAY_AFFILIATE_CAMPAIGN_ID", "cf-snipe-999")
+
+        def get_pref(user_id, path, default=None):
+            if path == "affiliate.opt_out":
+                return True
+            return default
+
+        result = wrap_url(
+            "https://www.ebay.com/itm/987654321",
+            retailer="ebay",
+            user_id="u99",
+            get_preference=get_pref,
+        )
+        assert result == "https://www.ebay.com/itm/987654321"
+
+    def test_disclosure_text_available(self):
+        text = get_disclosure_text("ebay")
+        assert "eBay" in text
+        assert len(text) > 20
+
+
+class TestAmazonIntegration:
+    def test_full_flow_with_env_var(self, monkeypatch):
+        monkeypatch.setenv("AMAZON_ASSOCIATES_TAG", "cf-kiwi-20")
+        url = wrap_url("https://www.amazon.com/dp/B00TEST1234", retailer="amazon")
+        assert "tag=cf-kiwi-20" in url
+
+    def test_preserves_existing_query_params(self, monkeypatch):
+        monkeypatch.setenv("AMAZON_ASSOCIATES_TAG", "cf-kiwi-20")
+        url = wrap_url(
+            "https://www.amazon.com/dp/B00TEST?ref=sr_1_1&keywords=flour",
+            retailer="amazon",
+        )
+        assert "tag=cf-kiwi-20" in url
+        assert "ref=sr_1_1" in url
+        assert "keywords=flour" in url
+
+
+class TestNoEnvVar:
+    def test_plain_url_returned_when_no_env_var(self, monkeypatch):
+        monkeypatch.delenv("EBAY_AFFILIATE_CAMPAIGN_ID", raising=False)
+        monkeypatch.delenv("AMAZON_ASSOCIATES_TAG", raising=False)
+        ebay_url = "https://www.ebay.com/itm/1"
+        amazon_url = "https://www.amazon.com/dp/B001"
+        assert wrap_url(ebay_url, retailer="ebay") == ebay_url
+        assert wrap_url(amazon_url, retailer="amazon") == amazon_url