qwen_agent/skills/common/mcp-ui/ui_render_server.py
2026-05-18 16:23:32 +08:00

149 lines
4.6 KiB
Python

#!/usr/bin/env python3
"""
MCP UI Server - provides interactive UI rendering tools.
"""
import asyncio
import json
import sys
from typing import Any, Dict
from mcp_common import (
create_error_response,
create_initialize_response,
create_ping_response,
create_tools_list_response,
load_tools_from_json,
handle_mcp_streaming,
)
ASK_USER_RESPONSE = "Questions sent to user."
def ask_user() -> Dict[str, Any]:
"""Return a minimal fixed response for ask_user tool.
The actual questions/options are already in the TOOL_CALL arguments,
so the frontend parses them directly from there. This response only
serves to acknowledge the tool call and minimize token usage in the
subsequent LLM inference round.
"""
return {
"content": [
{"type": "text", "text": ASK_USER_RESPONSE}
]
}
RENDER_UI_RESPONSE = "UI rendered."
def render_ui() -> Dict[str, Any]:
"""Return a minimal fixed response for render_ui tool.
The actual html_content/url is already in the TOOL_CALL arguments,
so the frontend parses them directly from there. This response only
serves to acknowledge the tool call and minimize token usage in the
subsequent LLM inference round.
"""
return {
"content": [
{"type": "text", "text": RENDER_UI_RESPONSE}
]
}
async def handle_request(request: Dict[str, Any]) -> Dict[str, Any]:
"""Handle an MCP request."""
try:
method = request.get("method")
params = request.get("params", {})
request_id = request.get("id")
if method == "initialize":
return create_initialize_response(request_id, "mcp-ui")
elif method == "ping":
return create_ping_response(request_id)
elif method == "tools/list":
tools = load_tools_from_json("mcp_ui_tools.json")
if not tools:
tools = [
{
"name": "render_ui",
"description": "Render an interactive UI widget in the chat.",
"inputSchema": {
"type": "object",
"properties": {
"title": {
"type": "string",
"description": "A descriptive title for the UI widget",
},
"html_content": {
"type": "string",
"description": "Complete HTML content to render. Use this OR url.",
},
"url": {
"type": "string",
"description": "External URL to embed. Use this OR html_content.",
},
},
"required": ["title"],
},
}
]
return create_tools_list_response(request_id, tools)
elif method == "tools/call":
tool_name = params.get("name")
arguments = params.get("arguments", {})
if tool_name == "render_ui":
html_content = arguments.get("html_content", "")
url = arguments.get("url", "")
if not html_content and not url:
return create_error_response(
request_id, -32602, "Missing required parameter: html_content or url"
)
result = render_ui()
return {"jsonrpc": "2.0", "id": request_id, "result": result}
elif tool_name == "ask_user":
questions = arguments.get("questions", [])
if not questions:
return create_error_response(
request_id, -32602, "Missing required parameter: questions"
)
result = ask_user()
return {"jsonrpc": "2.0", "id": request_id, "result": result}
else:
return create_error_response(
request_id, -32601, f"Unknown tool: {tool_name}"
)
else:
return create_error_response(
request_id, -32601, f"Unknown method: {method}"
)
except Exception as e:
return create_error_response(
request.get("id"), -32603, f"Internal error: {str(e)}"
)
async def main():
"""Main entry point."""
await handle_mcp_streaming(handle_request)
if __name__ == "__main__":
asyncio.run(main())