// ---------------------------------------------------------------------------// Extract the HTTP status from an MCP SDK transport error. The SDK surfaces// transport failures two ways: an `SdkHttpError` carrying a numeric `status`,// and an `SseError` carrying a numeric `code`. The SSE transport also retains// its historic POST-failure message for errors created below EventSource.// Shared by the invoke path (classifies tool-call failures) and the connect// path (so a 401/403 during the handshake reaches the liveness health check).// --------------------------------------------------------------------------- import { Option, Schema } from "effect"; import { insufficientScopeFromEmbeddedJson } from "@executor-js/sdk/core";// The SDK error classes are reached through the lazy loader: any error of// those classes was constructed by the loaded client module, so "not loaded"// soundly classifies the cause as not-an-SDK-error (see client-module.ts).import { mcpClientSdkIfLoaded } from "./client-module"; const SsePostErrorCause = Schema.Struct({ message: Schema.String });const decodeSsePostErrorCause = Schema.decodeUnknownOption(SsePostErrorCause); // V2 still constructs this exact message in SSEClientTransport._send. A format// drift just yields undefined (generic error, no crash).const statusFromSsePostError = (cause: unknown): number | undefined =>  Option.match(decodeSsePostErrorCause(cause), {    onNone: () => undefined,    onSome: ({ message }) => {      const match = /^Error POSTing to endpoint \(HTTP ([1-5][0-9]{2})\):/.exec(message);      if (!match) return undefined;      return Number(match[1]);    },  }); const statusFromTypedTransportError = (cause: unknown): number | undefined => {  const sdk = mcpClientSdkIfLoaded();  if (sdk === undefined) return undefined;  if (sdk.client.SdkHttpError.isInstance(cause)) return cause.status;  if (sdk.client.SseError.isInstance(cause)) {    const code = cause.code;    return code !== undefined && code >= 100 && code <= 599 ? code : undefined;  }  return undefined;}; export const httpStatusFromCause = (cause: unknown): number | undefined =>  statusFromTypedTransportError(cause) ?? statusFromSsePostError(cause); // The SDK embeds the upstream response text in the transport error message// ("Error POSTing to endpoint: <body>"), which is the only place a 403's body// survives for connections without an authProvider. For OAuth connections the// StreamableHTTP transport consumes the insufficient_scope challenge itself.// V2 throws `InsufficientScopeError` when configured not to reauthorize; after// exhausting its step-up retries it throws `SdkHttpError` with the exact fixed// message matched below (verified against the installed v2 transport source).// Both paths mean the same thing: the grant does not cover the operation, and// re-running the identical flow cannot help. Strict matching// (exact serialized field forms via the shared core detector, or the SDK's// exact step-up message) — a miss stays on the generic auth path.const SDK_STEP_UP_EXHAUSTED_RE =  /^Server returned 403 insufficient_scope after step-up re-authorization \(retry limit \d+ reached\)$/; export const insufficientScopeFromCause = (cause: unknown): boolean =>  (mcpClientSdkIfLoaded()?.client.InsufficientScopeError.isInstance(cause) ?? false) ||  Option.match(decodeSsePostErrorCause(cause), {    onNone: () => false,    onSome: ({ message }) =>      insufficientScopeFromEmbeddedJson(message) || SDK_STEP_UP_EXHAUSTED_RE.test(message),  });