API response invalid JSON: validate before you map fields
Clients often assume 200 responses are JSON. When the server returns HTML or plain text errors, JSON.parse throws. Validate the response body before mapping fields to avoid partial crashes and retries.
Common causes
- Error page with 200 status.
- Chunked truncation or gzip issues.
- Mixed content with debug stack traces.
How to fix
- Use API Response Analyzer to sanity-check status and body shape.
- Run Request Body Validator on the body substring.
- Treat non-JSON as a hard failure path in the client.
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Analyze API responseRelated