#!/usr/bin/env python3 """Stdio MCP module letting an agent rearrange the canvas AFTER spawn (ENG-334). One tool, CanvasCommand, backed by /api/canvas/command, which relays to the renderer over the browser-command bridge. Placement at spawn already existed; this adds move/collapse/expand/tile/close/tidy so an agent can park its browser next to its chat, shrink itself when done, or clean up a helper card it opened. Close is enforced server-side to the caller's own card or cards it spawned.""" import json import os import sys import urllib.error import urllib.request BACKEND_PORT = os.environ.get("OPENSWARM_PORT", "8324") BACKEND_AUTH = os.environ.get("OPENSWARM_AUTH_TOKEN", "") BACKEND_URL = f"http://127.0.0.1:{BACKEND_PORT}/api/canvas/command" PARENT_SESSION_ID = os.environ.get("OPENSWARM_PARENT_SESSION_ID", "") DASHBOARD_ID = os.environ.get("OPENSWARM_DASHBOARD_ID", "") TOOLS = [ { "name": "CanvasCommand", "description": ( "Control cards on the user's canvas after they exist: move a card, collapse or " "expand it, tile it to a screen zone, close it, or tidy the whole board. " "card_id defaults to YOUR own chat card; use a browser card's id (from " "CreateBrowserAgent) or a child session id to control cards you spawned. " "Closing is limited to your own card and cards you spawned. Use this sparingly " "and purposefully: the canvas belongs to the user, so rearrange only when it " "clearly helps the task (e.g. tuck your browser beside your chat, close a " "helper you no longer need, tidy after spawning several cards)." ), "inputSchema": { "type": "object", "properties": { "action": { "type": "string", "enum": ["move", "collapse", "expand", "tile", "close", "tidy"], "description": "What to do. tidy reflows every card on the board and ignores card_id.", }, "card_id": { "type": "string", "description": "Target card: an agent session id, browser card id, app/view card id, or workflow card id. Defaults to your own card.", }, "x": {"type": "number", "description": "move only: canvas x."}, "y": {"type": "number", "description": "move only: canvas y."}, "zone": { "type": "string", "enum": ["fill", "left", "right", "top", "bottom", "tl", "tr", "bl", "br", "fullscreen", "restore"], "description": "tile only: which screen zone; restore un-tiles.", }, }, "required": ["action"], "additionalProperties": False, }, }, ] def send_response(id_, result=None, error=None): msg = {"jsonrpc": "2.0", "id": id_} if error is not None: msg["error"] = error else: msg["result"] = result sys.stdout.write(json.dumps(msg) + "\n") sys.stdout.flush() def call_backend(payload: dict) -> dict: full = {**payload, "parent_session_id": PARENT_SESSION_ID, "dashboard_id": DASHBOARD_ID} body = json.dumps(full).encode() headers = {"Content-Type": "application/json"} if BACKEND_AUTH: headers["Authorization"] = f"Bearer {BACKEND_AUTH}" req = urllib.request.Request(BACKEND_URL, data=body, headers=headers, method="POST") try: with urllib.request.urlopen(req, timeout=30) as resp: return json.loads(resp.read().decode()) except urllib.error.HTTPError as e: detail = e.read().decode() if e.fp else str(e) return {"error": f"HTTP {e.code}: {detail}"} except Exception as e: return {"error": str(e)} def handle_tool_call(tool_name: str, arguments: dict) -> dict: if tool_name != "CanvasCommand": return {"content": [{"type": "text", "text": f"Unknown tool: {tool_name}"}], "isError": True} action = str(arguments.get("action") or "").strip() if not action: return {"content": [{"type": "text", "text": "Error: `action` is required."}], "isError": True} payload = { "action": action, "card_id": str(arguments.get("card_id") or ""), } if arguments.get("x") is not None: payload["x"] = arguments.get("x") if arguments.get("y") is not None: payload["y"] = arguments.get("y") if arguments.get("zone"): payload["zone"] = str(arguments.get("zone")) result = call_backend(payload) if isinstance(result, dict) and result.get("error"): return {"content": [{"type": "text", "text": f"Error: {result['error']}"}], "isError": True} text = result.get("text") if isinstance(result, dict) else None return {"content": [{"type": "text", "text": str(text or "Done.")}]} def main(): for line in sys.stdin: line = line.strip() if not line: continue try: msg = json.loads(line) except json.JSONDecodeError: continue method = msg.get("method") id_ = msg.get("id") params = msg.get("params", {}) if method == "initialize": send_response(id_, { "protocolVersion": "2024-11-05", "capabilities": {"tools": {}}, "serverInfo": {"name": "openswarm-canvas", "version": "1.0.0"}, }) elif method == "notifications/initialized": pass elif method == "tools/list": send_response(id_, {"tools": TOOLS}) elif method == "tools/call": tool_name = params.get("name", "") arguments = params.get("arguments", {}) try: send_response(id_, handle_tool_call(tool_name, arguments)) except Exception as e: send_response(id_, error={"code": -32000, "message": str(e)}) elif method == "resources/list": send_response(id_, {"resources": []}) elif method == "prompts/list": send_response(id_, {"prompts": []}) elif id_ is not None: send_response(id_, error={"code": -32601, "message": f"Method not found: {method}"}) if __name__ == "__main__": main()