Fix No-JS Fallback Checker Setup Issues
No-JS Fallback Checker can return weak or inconsistent output when the target URL, crawler access, or baseline metadata is misconfigured. Use this checklist to stabilize setup before deeper analysis.
Common causes
- Wrong URL format or mixed protocol variants (http/https).
- Important paths blocked in robots or by firewall/CDN rules.
- Missing baseline assets (llms.txt, tools.json, sitemap, schema).
How to fix
- Normalize URL and test canonical destination first.
- Allow required bot/user-agent access for this check path.
- Re-run after baseline files are reachable and return 200.
Common errors
ValidationError: Invalid input payload in no-js-fallback-checkerFetchError: Timeout while requesting target URL for no-js-fallback-checkerParseError: Unsupported response format detected by no-js-fallback-checker
FAQ
- Why does No-JS Fallback Checker return weak results?
- Weak results usually indicate missing baseline signals (crawlability, schema, or clean input). Validate prerequisites and rerun the check.
- How do I improve No-JS Fallback Checker reliability in production?
- Use stable URLs, valid structured data, and consistent machine-readable files. Re-test after each fix to confirm signal improvement.
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