firecrawl/open-lovable · error

Failed to generate code

Error message

Failed to generate code

What it means

Thrown when the AI code-generation streaming endpoint returns a non-2xx status or a response without a readable body (aiResponse.ok === false || !aiResponse.body). The clone/brand generation request failed before any streamed code or explanation could be read, so the generation flow aborts. Note !response.body also fires on opaque or body-less responses even when status is OK.

Source

Thrown at app/generation/page.tsx:3032

          lastProcessedPosition: 0
        }));
        
        const aiResponse = await fetch('/api/generate-ai-code-stream', {
          method: 'POST',
          headers: { 'Content-Type': 'application/json' },
          body: JSON.stringify({ 
            prompt,
            model: aiModel,
            context: {
              sandboxId: sandboxData?.sandboxId,
              structure: structureContent,
              conversationContext: conversationContext
            }
          })
        });
        
        if (!aiResponse.ok || !aiResponse.body) {
          throw new Error('Failed to generate code');
        }
        
        const reader = aiResponse.body.getReader();
        const decoder = new TextDecoder();
        let generatedCode = '';
        let explanation = '';
        
        while (true) {
          const { done, value } = await reader.read();
          if (done) break;
          
          const chunk = decoder.decode(value);
          const lines = chunk.split('\n');
          
          for (const line of lines) {
            if (line.startsWith('data: ')) {
              try {
                const data = JSON.parse(line.slice(6));

View on GitHub (pinned to 69bd93bae7)

Solutions

1. Inspect the failed generation request's status and body in the Network tab for the server-side reason
2. Verify the LLM API key, quota, and rate limits server-side if the status is 401/402/429
3. Trim conversationContext/scrapedWebsites to shrink the prompt if you hit 413 or context-length errors
4. Confirm the route exists and that no proxy strips the response body (test streaming via curl)
5. Retry with exponential backoff for 429/5xx; check aiResponse.body nullability to distinguish no-stream from HTTP failure

Example fix

// before
if (!aiResponse.ok || !aiResponse.body) {
  throw new Error('Failed to generate code');
}
// after
if (!aiResponse.ok || !aiResponse.body) {
  let detail = '';
  try { detail = await aiResponse.text(); } catch {}
  const cause = !aiResponse.ok
    ? `HTTP ${aiResponse.status}: ${detail || aiResponse.statusText}`
    : 'response has no readable body stream';
  throw new Error(`Failed to generate code (${cause})`);
}

const res = await fetch(GENERATION_URL, { method: 'POST', body: JSON.stringify(payload) });
if (!res.ok) throw new Error(`Generation HTTP ${res.status}: ${await res.text().catch(() => res.statusText)}`);
if (!res.body) throw new Error('Generation response has no body stream — check proxy/streaming support');

function isStreamable(r: Response): r is Response & { ok: true; body: ReadableStream<Uint8Array> } {
  return r.ok && r.body !== null && typeof r.body.getReader === 'function';
}

async function generateStream(payload: unknown, retries = 3): Promise<Response> {
  for (let attempt = 0; attempt < retries; attempt++) {
    const res = await fetch(GENERATION_URL, { method: 'POST', body: JSON.stringify(payload) });
    if (isStreamable(res)) return res;
    const detail = await res.text().catch(() => '');
    const retryable = [429, 500, 502, 503, 504].includes(res.status);
    if (!retryable || attempt === retries - 1) {
      throw new Error(`Failed to generate code (${res.status}): ${detail || res.statusText}`);
    }
    await new Promise(r => setTimeout(r, 2 ** attempt * 1000));
  }
  throw new Error('unreachable');
}

When it happens

Trigger: fetch to the generation route (with scraped content, brand guidelines, conversationContext) resolves with ok === false (route validation failure, upstream LLM error, missing route) OR resolves with no body stream (proxies stripping the body, unsupported streaming in the environment, opaque cross-origin response).

Common situations: LLM provider key/quota problems (401/402/429) after a long scraping session; oversized prompt from accumulated scrapedWebsites exceeding model context or body limits (413); environment without streaming support (older browsers/proxies buffering responses); generation route missing after a redeploy; streaming disabled by an intermediary.

Related errors

• HTTP error! status: ${response.status}
• Failed to apply code: ${response.statusText}
• Firecrawl API returned ${firecrawlResponse.status}
• Failed to extract brand styles
• Failed to scrape website

AI-assisted analysis of firecrawl/open-lovable@69bd93bae7 (2026-08-28). Data as JSON: /api/errors/00451c396c2d0d9b. Report an issue: GitHub.