Firecrawl Common Errors

Overview

Quick-reference diagnostic guide for the most common Firecrawl API errors. Covers HTTP status codes, SDK exceptions, empty content, and crawl job failures with concrete fixes.

Prerequisites

• Firecrawl SDK installed (@mendable/firecrawl-js)
• FIRECRAWL_API_KEY environment variable set
• Access to error logs or console output

Error Reference

401 Unauthorized — Invalid API Key

Error: Unauthorized. Invalid API key.

Cause: API key is missing, malformed, or revoked.

set -euo pipefail
# Verify key is set and starts with fc-
echo "Key prefix: ${FIRECRAWL_API_KEY:0:3}"

# Test directly
curl -s https://api.firecrawl.dev/v1/scrape \
  -H "Authorization: Bearer $FIRECRAWL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"url":"https://example.com","formats":["markdown"]}' | jq .success

Fix: Regenerate key at firecrawl.dev/app. Ensure it starts with fc-.

402 Payment Required — Credits Exhausted

Error: Payment required. You have exceeded your credit limit.

Cause: Monthly or plan credits are used up.

set -euo pipefail
# Check remaining credits
curl -s https://api.firecrawl.dev/v1/team/credits \
  -H "Authorization: Bearer $FIRECRAWL_API_KEY" | jq .

Fix: Upgrade plan or wait for monthly credit reset. Failed requests do not consume credits.

429 Too Many Requests — Rate Limited

Error: Rate limit exceeded. Retry after X seconds.

Cause: Too many concurrent requests or requests per minute.

// Fix: implement exponential backoff
async function scrapeWithBackoff(url: string, retries = 3) {
  for (let i = 0; i < retries; i++) {
    try {
      return await firecrawl.scrapeUrl(url, { formats: ["markdown"] });
    } catch (err: any) {
      if (err.statusCode !== 429 || i === retries - 1) throw err;
      const delay = 1000 * Math.pow(2, i);
      console.warn(`Rate limited, retrying in ${delay}ms...`);
      await new Promise(r => setTimeout(r, delay));
    }
  }
}

Fix: Respect Retry-After header. Queue requests with p-queue.

Empty Markdown — JS Content Not Rendered

const result = await firecrawl.scrapeUrl("https://spa-app.com");
console.log(result.markdown); // "" or just nav text

Cause: Single-page app or JS-heavy site needs time to render.

// Fix: add waitFor and use actions for dynamic content
const result = await firecrawl.scrapeUrl("https://spa-app.com", {
  formats: ["markdown"],
  waitFor: 5000,  // wait 5s for JS rendering
  onlyMainContent: true,
});

Crawl Returns Zero Pages

const crawl = await firecrawl.crawlUrl("https://example.com/docs", {
  includePaths: ["/api/*"],
});
// crawl.data is empty

Cause: Start URL does not match includePaths pattern, or paths are too restrictive.

// Fix: ensure start URL matches include patterns
const crawl = await firecrawl.crawlUrl("https://example.com", {
  includePaths: ["/docs/*", "/api/*"],  // start URL must match too
  limit: 50,
});

Crawl Stuck at "scraping" Status

const status = await firecrawl.checkCrawlStatus(jobId);
// status.status === "scraping" for >10 minutes

Cause: Large site, slow JS rendering, or Firecrawl queue backup.

// Fix: set timeout and fall back to individual scrapes
const TIMEOUT_MS = 600000; // 10 minutes
const deadline = Date.now() + TIMEOUT_MS;

while (Date.now() < deadline) {
  const status = await firecrawl.checkCrawlStatus(jobId);
  if (status.status === "completed") return status;
  if (status.status === "failed") throw new Error(status.error);
  await new Promise(r => setTimeout(r, 5000));
}
throw new Error("Crawl timed out — try reducing limit or using scrapeUrl");

MODULE_NOT_FOUND — Wrong Package Name

Error: Cannot find module '@firecrawl/sdk'

Cause: Using wrong npm package name.

set -euo pipefail
# The correct package is @mendable/firecrawl-js
npm install @mendable/firecrawl-js

Import: import FirecrawlApp from "@mendable/firecrawl-js"

Quick Diagnostic

set -euo pipefail
# 1. Check Firecrawl API health
curl -s https://api.firecrawl.dev/v1/scrape \
  -H "Authorization: Bearer $FIRECRAWL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"url":"https://example.com","formats":["markdown"]}' | jq '{success, markdown_length: (.markdown | length)}'

# 2. Verify SDK version
npm list @mendable/firecrawl-js 2>/dev/null

# 3. Check env var
env | grep FIRECRAWL

Error Handling

Examples

Comprehensive Error Handler

async function safeScrape(url: string) {
  try {
    return await firecrawl.scrapeUrl(url, { formats: ["markdown"] });
  } catch (err: any) {
    const status = err.statusCode;
    if (status === 401) console.error("Invalid API key");
    else if (status === 402) console.error("Credits exhausted");
    else if (status === 429) console.error("Rate limited — retry later");
    else console.error(`Firecrawl error ${status}:`, err.message);
    return null;
  }
}

Resources

• Firecrawl API Reference
• Rate Limits
• Firecrawl Dashboard

Next Steps

For comprehensive debugging, see firecrawl-debug-bundle.