fix(tools): strip default from $ref nodes in tool schemas

Fireworks-hosted Kimi rejects tool requests when nullable MCP/Pydantic schemas collapse to {"$ref": "...", "default": null}. Strip that sibling during global schema sanitization so gateway and CLI calls succeed again.
2026-06-12 00:30:51 -05:00
parent c574170050
commit b2d151abe2
2 changed files with 104 additions and 0 deletions
@@ -201,6 +201,72 @@ def test_items_sanitized_in_array_schema():
    assert items == {"type": "object", "properties": {}}


+def test_ref_with_default_sibling_stripped():
+    """Strict backends reject ``default`` alongside ``$ref``."""
+    tools = [_tool("t", {
+        "type": "object",
+        "properties": {
+            "payload": {"$ref": "#/$defs/Payload", "default": None},
+        },
+        "$defs": {
+            "Payload": {
+                "type": "object",
+                "properties": {"q": {"type": "string"}},
+            },
+        },
+    })]
+    out = sanitize_tool_schemas(tools)
+    payload = out[0]["function"]["parameters"]["properties"]["payload"]
+    assert payload == {"$ref": "#/$defs/Payload"}
+
+
+def test_nullable_union_collapse_does_not_leave_default_on_ref():
+    """Nullable anyOf collapse must not attach ``default`` to a ``$ref`` branch."""
+    tools = [_tool("t", {
+        "type": "object",
+        "properties": {
+            "input": {
+                "anyOf": [
+                    {"$ref": "#/$defs/Payload"},
+                    {"type": "null"},
+                ],
+                "default": None,
+            },
+        },
+        "$defs": {
+            "Payload": {
+                "type": "object",
+                "properties": {"q": {"type": "string"}},
+            },
+        },
+    })]
+    out = sanitize_tool_schemas(tools)
+    prop = out[0]["function"]["parameters"]["properties"]["input"]
+    assert prop["$ref"] == "#/$defs/Payload"
+    assert "default" not in prop
+    assert prop.get("nullable") is True
+
+
+def test_ref_description_preserved():
+    """Annotation siblings that strict backends allow should survive."""
+    tools = [_tool("t", {
+        "type": "object",
+        "properties": {
+            "payload": {
+                "$ref": "#/$defs/Payload",
+                "description": "The payload",
+            },
+        },
+        "$defs": {
+            "Payload": {"type": "object", "properties": {}},
+        },
+    })]
+    out = sanitize_tool_schemas(tools)
+    payload = out[0]["function"]["parameters"]["properties"]["payload"]
+    assert payload["description"] == "The payload"
+    assert payload["$ref"] == "#/$defs/Payload"
+
+
 def test_empty_tools_list_returns_empty():
    assert sanitize_tool_schemas([]) == []