fix(client-runtime): relay disconnects no longer show as thread errors (pingdotgg#15470)

Co-authored-by: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: juliusmarminge

packages/client-runtime/src/errors/transport.test.ts

@@ -1,5 +1,6 @@
 import { describe, expect, it } from "vite-plus/test";
 
+import { NETWORK_BLOCKING_HINT } from "./network.ts";
 import { isTransportConnectionErrorMessage, sanitizeThreadErrorMessage } from "./transport.ts";
 
 describe("isTransportConnectionErrorMessage", () => {
@@ -30,6 +31,20 @@ describe("isTransportConnectionErrorMessage", () => {
     expect(isTransportConnectionErrorMessage("ClientProtocolError: socket closed")).toBe(true);
   });
 
+  it("recognizes relay connection errors that carry the network hint", () => {
+    for (const sentence of [
+      "Relay environment disconnected.",
+      "Relay environment could not establish a WebSocket connection.",
+    ]) {
+      expect(isTransportConnectionErrorMessage(`${sentence} ${NETWORK_BLOCKING_HINT}`)).toBe(true);
+    }
+    expect(
+      isTransportConnectionErrorMessage(
+        "Your ChatGPT connection expired or was disconnected. Sign in again.",
+      ),
+    ).toBe(false);
+  });
+
   it("returns true for the T3 server WebSocket message", () => {
     expect(isTransportConnectionErrorMessage("Unable to connect to the T3 server WebSocket.")).toBe(
       true,

packages/client-runtime/src/errors/transport.ts

@@ -1,11 +1,18 @@
+import { NETWORK_BLOCKING_HINT } from "./network.ts";
+
+const escapeRegExp = (text: string) => text.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
+
 const TRANSPORT_ERROR_PATTERNS = [
   /\bSocketCloseError\b/i,
   /\bSocketOpenError\b/i,
   /\bSocket is not connected\b/i,
   /Unable to connect to the T3 server WebSocket\./i,
-  /\bis not connected\.$/i,
-  /\bdisconnected\.$/i,
-  /\bcould not establish a WebSocket connection\.$/i,
+  // The RPC session appends the network hint for relay connections. Any other
+  // trailing text means a different error that the user should still see.
+  new RegExp(
+    `\\b(?:is not connected|disconnected|could not establish a WebSocket connection)\\.(?: ${escapeRegExp(NETWORK_BLOCKING_HINT)})?$`,
+    "i",
+  ),
   /\bClientProtocolError\b/i,
   /\bRpcClientError\b/i,
   /\bping timeout\b/i,