Add parameter schema and defaults to ToolResource model and schemas. Implement runtime tool resolution in assistants and tools routers, ensuring proper handling of tool parameters. Update tests to validate new functionality and ensure correct integration of parameter handling in the API.

engine/tests/test_tool_call_flow.py

@@ -1,4 +1,5 @@
 import asyncio
+import json
 from typing import Any, Dict, List
 
 import pytest
@@ -143,6 +144,64 @@ def test_pipeline_assigns_default_client_executor_for_system_string_tools(monkey
     assert pipeline._tool_executor(tool_call) == "client"
 
 
+@pytest.mark.asyncio
+async def test_pipeline_applies_default_args_to_tool_call(monkeypatch):
+    pipeline, _events = _build_pipeline(
+        monkeypatch,
+        [
+            [
+                LLMStreamEvent(
+                    type="tool_call",
+                    tool_call={
+                        "id": "call_defaults",
+                        "type": "function",
+                        "function": {"name": "weather", "arguments": "{}"},
+                    },
+                ),
+                LLMStreamEvent(type="done"),
+            ],
+            [LLMStreamEvent(type="done")],
+        ],
+    )
+    pipeline.apply_runtime_overrides(
+        {
+            "tools": [
+                {
+                    "type": "function",
+                    "executor": "server",
+                    "defaultArgs": {"city": "Hangzhou", "unit": "c"},
+                    "function": {
+                        "name": "weather",
+                        "description": "Get weather",
+                        "parameters": {"type": "object", "properties": {"city": {"type": "string"}}},
+                    },
+                }
+            ]
+        }
+    )
+
+    captured: Dict[str, Any] = {}
+
+    async def _server_exec(call: Dict[str, Any]) -> Dict[str, Any]:
+        captured["call"] = call
+        return {
+            "tool_call_id": str(call.get("id") or ""),
+            "name": "weather",
+            "output": {"ok": True},
+            "status": {"code": 200, "message": "ok"},
+        }
+
+    monkeypatch.setattr(pipeline, "_server_tool_executor", _server_exec)
+    await pipeline._handle_turn("weather?")
+
+    sent_call = captured.get("call")
+    assert isinstance(sent_call, dict)
+    args_raw = sent_call.get("function", {}).get("arguments")
+    args = json.loads(args_raw) if isinstance(args_raw, str) else {}
+    assert args.get("city") == "Hangzhou"
+    assert args.get("unit") == "c"
+
+
 @pytest.mark.asyncio
 async def test_ws_message_parses_tool_call_results():
     msg = parse_client_message(