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408Retryable

Google Gemini 408 Request Timeout

The connection idled out before the request completed — typically network-level rather than model-level on the Gemini API.

Most likely causes

  1. 1.Slow upload of large inline payloads
  2. 2.Proxy/VPN adding latency past the timeout

Fix checklist

  • Upload media via the Files API first, then reference it
  • Retry on a better network path; keep request bodies small

Retry guidance

Retry with backoff from 1s, 3 attempts.

// Retry 408 with exponential backoff + full jitter.
async function callWithBackoff(payload: unknown, maxAttempts = 5) {
  for (let attempt = 0; attempt < maxAttempts; attempt++) {
    const res = await fetch("https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-pro:generateContent", {
      method: "POST",
      headers: {
        "content-type": "application/json",
        "x-goog-api-key": process.env.GEMINI_API_KEY!,
      },
      body: JSON.stringify(payload),
    });
    if (res.status !== 408) return res;
    // Honor Retry-After when present; otherwise exponential backoff, capped at 32s.
    const retryAfter = Number(res.headers.get("retry-after"));
    const base = Number.isFinite(retryAfter) && retryAfter > 0
      ? retryAfter * 1000
      : Math.min(1000 * 2 ** attempt, 32_000);
    await new Promise((r) => setTimeout(r, base * (0.5 + Math.random() * 0.5)));
  }
  throw new Error("Google Gemini 408: still failing after backoff — check https://status.cloud.google.com");
}

Provider status page: status.cloud.google.com