From 700be68a38c5e99cde21029af9716965c08bdbfa Mon Sep 17 00:00:00 2001
From: Ishaan Jaffer <ishaanjaffer0324@gmail.com>
Date: Tue, 10 Feb 2026 16:45:05 -0800
Subject: [PATCH] TestMatchAttribution

---
 .../policy_engine/test_attachment_registry.py | 61 +++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/tests/test_litellm/proxy/policy_engine/test_attachment_registry.py b/tests/test_litellm/proxy/policy_engine/test_attachment_registry.py
index ab1ed925e2e..c853253eedd 100644
--- a/tests/test_litellm/proxy/policy_engine/test_attachment_registry.py
+++ b/tests/test_litellm/proxy/policy_engine/test_attachment_registry.py
@@ -264,6 +264,67 @@ class TestTagBasedAttachments:
         assert "strict-policy" not in registry.get_attached_policies(context_wrong_tag)
 
 
+class TestMatchAttribution:
+    """Test get_attached_policies_with_reasons — the attribution logic that
+    powers response headers and the Policy Simulator UI."""
+
+    def test_reasons_for_global_tag_team_attachments(self):
+        """Test that match reasons correctly describe WHY each policy matched."""
+        registry = AttachmentRegistry()
+        registry.load_attachments([
+            {"policy": "global-baseline", "scope": "*"},
+            {"policy": "hipaa-policy", "tags": ["healthcare"]},
+            {"policy": "team-policy", "teams": ["health-team"]},
+        ])
+
+        context = PolicyMatchContext(
+            team_alias="health-team", key_alias="key", model="gpt-4",
+            tags=["healthcare"],
+        )
+        results = registry.get_attached_policies_with_reasons(context)
+        reasons = {r["policy_name"]: r["matched_via"] for r in results}
+
+        assert reasons["global-baseline"] == "scope:*"
+        assert "tag:healthcare" in reasons["hipaa-policy"]
+        assert "team:health-team" in reasons["team-policy"]
+
+    def test_tags_only_attachment_matches_any_team_key_model(self):
+        """Test the primary use case: tags-only attachment with no team/key/model
+        constraint matches any request that carries the tag."""
+        registry = AttachmentRegistry()
+        registry.load_attachments([
+            {"policy": "hipaa-guardrails", "tags": ["healthcare"]},
+        ])
+
+        # Should match regardless of team/key/model
+        context = PolicyMatchContext(
+            team_alias="random-team", key_alias="random-key", model="claude-3",
+            tags=["healthcare"],
+        )
+        attached = registry.get_attached_policies(context)
+        assert "hipaa-guardrails" in attached
+
+        # Should not match without the tag
+        context_no_tag = PolicyMatchContext(
+            team_alias="random-team", key_alias="random-key", model="claude-3",
+        )
+        assert registry.get_attached_policies(context_no_tag) == []
+
+    def test_attachment_with_no_scope_matches_everything(self):
+        """Test that an attachment with no scope/teams/keys/models/tags
+        matches everything because teams/keys/models default to ['*']."""
+        registry = AttachmentRegistry()
+        registry.load_attachments([
+            {"policy": "catch-all"},
+        ])
+
+        context = PolicyMatchContext(
+            team_alias="any-team", key_alias="any-key", model="gpt-4",
+        )
+        attached = registry.get_attached_policies(context)
+        assert "catch-all" in attached
+
+
 class TestAttachmentRegistrySingleton:
     """Test global singleton behavior."""