A dropped connection says so, instead of the generic error card

A user's run failed with the wizard's generic "check your Ollama
settings" card and could not be replicated with the same key - because
the key and model were never the problem: a raw error (a mid-run socket
drop, a wifi/LTE switch, the app backgrounded by the phone OS) leaked
out of the NDJSON reader as a DOMException, and the wizard can only
show the generic card for unknown errors.

The reader now classifies everything: abort -> "cancelled", stall ->
"the model stopped responding", anything else on the wire -> "the
connection dropped mid-run, try again". Pinned with a fetch stub that
kills the stream mid-run in the wizard suite (95 checks).

Contrast 0 findings, mobile 124/124, chat 101/101, regression 44/44,
i18n 13/13, native 33/33. Version 0.4.1, SW -> freezmo-v70.

README.md

@@ -1411,6 +1411,15 @@ Things I chose while building, with the reasoning:
     pre-blurred wallpaper — the scene is clearly visible through the glass, and the
     pixel-contrast scan still passes.
 
+76. **A dropped connection says so.** A user's run failed with the wizard's generic "check your
+    Ollama settings" card, and it could not be replicated on the owner's machine with the same key
+    — because the key and model were never the problem. A raw error (a mid-run socket drop, a
+    wifi/LTE switch, an app backgrounded by the phone OS) leaked out of the NDJSON reader as a
+    DOMException, and the wizard can only show that generic card for unknown errors. The reader now
+    classifies everything: an abort is "cancelled", a stall is "the model stopped responding", and
+    anything else on the wire is "the connection dropped mid-run — try again". Pinned with a
+    fetch stub that kills the stream mid-run in the wizard suite (95 checks).
+
 75. **A quiet run can no longer load forever.** A user got stuck on the wizard's loading screen:
     a hung model meant silence, and silence was indistinguishable from work — the server's own hard
     deadline is 2x `OLLAMA_TIMEOUT_MS` (ten minutes by default), and the client waited on a dead

lib/client-api.ts

@@ -76,22 +76,29 @@ export async function consumeNdjson(
   };
   while (true) {
     let chunk: ReadableStreamReadResult<Uint8Array>;
-    if (stallMs > 0) {
     let timer: ReturnType<typeof setTimeout> | null = null;
+    try {
+      if (stallMs > 0) {
         const stalled = new Promise<never>((_, reject) => {
           timer = setTimeout(() => reject(new ApiError(t("api.stalled"), "timeout")), stallMs);
         });
-      try {
         chunk = await Promise.race([reader.read(), stalled]);
-      } catch (error) {
-        void reader.cancel().catch(() => {});
-        throw error;
-      } finally {
-        if (timer) clearTimeout(timer);
-      }
       } else {
         chunk = await reader.read();
       }
+    } catch (error) {
+      // A connection that dropped mid-run used to leak a raw DOMException, and
+      // the wizard answered with its generic "check your Ollama settings"
+      // card for what was really a network blip. Classify everything here.
+      void reader.cancel().catch(() => {});
+      if (error instanceof ApiError) throw error;
+      if (error instanceof Error && error.name === "AbortError") {
+        throw new ApiError(t("api.cancelled"), "aborted");
+      }
+      throw new ApiError(t("api.streamLost"), "network");
+    } finally {
+      if (timer) clearTimeout(timer);
+    }
     if (chunk.done) break;
     buffer += decoder.decode(chunk.value, { stream: true });
     let newline = buffer.indexOf("\n");

lib/i18n-dict.ts

@@ -721,6 +721,7 @@ const en: Record<string, string> = {
   "api.httpError": "The server returned HTTP {status}.",
   "api.empty": "The server sent an empty response.",
   "api.stalled": "The model stopped responding. Check it and try again.",
+  "api.streamLost": "The connection dropped mid-run. Check your connection and try again.",
   "api.almost": "Almost there…",
   "api.noDeck": "No deck came back from the server. Check your Ollama settings and try again.",
   "api.incomplete": "The server finished without sending a deck.",
@@ -1677,6 +1678,7 @@ const cs: Record<string, string> = {
   "api.httpError": "Server vrátil HTTP {status}.",
   "api.empty": "Server poslal prázdnou odpověď.",
   "api.stalled": "Model přestal odpovídat. Zkontrolujte ho a zkuste to znovu.",
+  "api.streamLost": "Připojení se během generování přerušilo. Zkontrolujte připojení a zkuste to znovu.",
   "api.almost": "Už to bude…",
   "api.noDeck": "Ze serveru nepřišla žádná sada. Zkontroluj nastavení Ollamy a zkus to znovu.",
   "api.incomplete": "Server skončil, aniž by poslal sadu.",

package.json

@@ -1,6 +1,6 @@
 {
   "name": "freezmo",
-  "version": "0.4.0",
+  "version": "0.4.1",
   "private": true,
   "license": "GPL-3.0-only",
   "scripts": {

public/sw.js

@@ -9,7 +9,7 @@
  *
  * Bumping CACHE_VERSION is how a new deploy invalidates old assets.
  */
-const CACHE_VERSION = "freezmo-v69";
+const CACHE_VERSION = "freezmo-v70";
 const SHELL_CACHE = `${CACHE_VERSION}-shell`;
 const ASSET_CACHE = `${CACHE_VERSION}-assets`;
 

tests/wizard-test.mjs

@@ -225,6 +225,44 @@ for (const viewport of [{ width: 390, height: 844 }, { width: 360, height: 740 }
   await context.close();
 }
 
+/* 4c. a dropped stream gets its own message, not the generic card ----- */
+{
+  const { context, page } = await makePage(browser);
+  await seed(page, { decks: [] });
+  await page.addInitScript(() => {
+    const original = window.fetch;
+    window.fetch = (input, init) => {
+      const url = typeof input === "string" ? input : input instanceof URL ? input.toString() : input.url;
+      if (!url.includes("/api/generate")) return original(input, init);
+      const encoder = new TextEncoder();
+      const stream = new ReadableStream({
+        start(controller) {
+          controller.enqueue(
+            encoder.encode(`${JSON.stringify({ type: "stage", stage: "generation", message: "Finding the key ideas…" })}\n`),
+          );
+          setTimeout(() => controller.error(new Error("socket dropped")), 300);
+        },
+      });
+      return Promise.resolve(new Response(stream, { status: 200, headers: { "Content-Type": "application/x-ndjson" } }));
+    };
+  });
+
+  await page.goto(`${BASE}/create`, { waitUntil: "networkidle" });
+  await page.waitForTimeout(300);
+  await page.getByRole("button", { name: "Paste text instead" }).click();
+  await page.locator("textarea").first().fill("Photosynthesis needs light and water.");
+  await page.getByRole("button", { name: "Next" }).click();
+  await page.getByRole("button", { name: "Next" }).click();
+  await page.getByRole("button", { name: "Freeze my deck" }).click();
+  await page.waitForTimeout(1400);
+  check(
+    "stream loss: the wizard explains the dropped connection",
+    await page.getByText("The connection dropped mid-run").isVisible(),
+  );
+  check("stream loss: retry is offered", await page.getByRole("button", { name: "Retry" }).isVisible());
+  await context.close();
+}
+
 /* 5. leaving mid-run aborts: no surprise deck, no navigation --------- */
 {
   const { context, page } = await makePage(browser);