Introduce an isError flag and propagate it through RPC responses, including initialize and action listings. Add a new action "evaluate_js_es3" with an input schema that accepts a script string and a handler that evaluates the script (returns the evaluation result as text or "Error" on exception). Also set isError for unknown methods so the RPC indicates failures consistently.
Treat a callback returning false as a signal to suppress a JSON-RPC reply (jsonrpc2.extract). Add a special-case in mcploader to return false for "notifications/initialized" so no response is sent. In stdio-server, skip sending falsy messages, keep object serialization, and write outgoing messages to both StdOut and StdErr (useful for logging/debugging). Small cleanup in catch formatting.
Implement MCP JSON-RPC handling and related I/O fixes: mcploader now handles initialize, tools/list and tools/call (implements add_both_numbers) and returns JSON-RPC responses; stdio-server.send serializes object messages before writing; console logging on WScript now writes muted messages to StdErr; bump jsonrpc2 version to 0.1.7 and reformat extract(). These changes enable proper MCP capability negotiation, tool discovery and invocation over stdio.
Introduce a StdioServer module and mcploader entry script, and extend jsonrpc2 with an extract() helper. stdio-server.js provides an EventTarget-based wrapper for reading/writing via WScript stdio. mcploader.js uses the server and JsonRpc2.extract to parse incoming JSON-RPC messages and respond. Also change DEFAULT_JSONRPC2_URL to http://localhost:5555, export the new extract function, and bump jsonrpc2 version to 0.1.6.
