Encode a JSON-RPC message as a single newline-terminated frame.

declare function encodeFrame(message: JsonRpcMessage): string;

declare function isJsonRpcNotification(m: unknown): m is JsonRpcNotification;

declare function isJsonRpcRequest(m: unknown): m is JsonRpcRequest;

declare function makeError(id: JsonRpcId, code: number, message: string, data?: unknown): JsonRpcError;

declare function makeSuccess(id: JsonRpcId, result: unknown): JsonRpcSuccess;

Parse newline-delimited JSON-RPC frames out of a buffer. Returns parsed messages plus any leftover bytes. Tolerates blank lines.

declare function parseFrames(buffer: string): ParseResult;

Wire an EditorBridge to a JSON-RPC stdio loop. Returns immediately; reading happens via the stream listeners. Designed to be testable: pass in fake streams, call `feed(...)` directly, then assert on what was written.

declare function runStdioServer(bridge: EditorBridge, options?: StdioServerOptions): StdioServerHandle;

declare class McpServer

interface JsonRpcError

interface JsonRpcNotification

interface JsonRpcRequest

interface JsonRpcSuccess

interface McpContent

interface McpInitializeResult

MCP server core. Transport-agnostic — accepts a JsonRpcRequest, returns either a JsonRpcResponse or `null` (for notifications, which never reply).

Wraps an EditorBridge: tools/list returns the bridge's tool schemas in MCP shape; tools/call dispatches via executeToolCall and converts the AgentToolResult into MCP CallToolResult content.

interface McpServerOptions

interface McpToolDescriptor

interface McpToolsCallParams

interface McpToolsCallResult

interface McpToolsListResult

interface StdioServerHandle

interface StdioServerOptions extends McpServerOptions

MCP wire protocol (subset) — JSON-RPC 2.0 framing + the message types we actually implement. Zero dependencies. Pure functions; everything is unit- testable without a transport.

This is NOT a full MCP SDK. We implement only what the server needs: - initialize / initialized - tools/list - tools/call - notifications/cancelled (no-op, accepted)

Spec reference: https://spec.modelcontextprotocol.io

type JsonRpcId = string | number | null;

type JsonRpcMessage = JsonRpcRequest | JsonRpcNotification | JsonRpcResponse;

type JsonRpcResponse = JsonRpcSuccess | JsonRpcError;

Standard JSON-RPC error codes. We only ever emit JSON-RPC errors for protocol-level problems; tool execution failures use MCP's `isError` envelope inside a successful response, per spec.

ErrorCode: {
    readonly ParseError: -32700;
    readonly InvalidRequest: -32600;
    readonly MethodNotFound: -32601;
    readonly InvalidParams: -32602;
    readonly InternalError: -32603;
}