Troubleshooting: Zapier webhooks failing when calling ChatGPT API
My Zapier webhook returns 400 when forwarding form data to ChatGPT — need common causes and fixes for API integration issues.
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Answers
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Common causes for 400 when a Zapier webhook forwards form data to ChatGPT — fixes:
- Malformed JSON: send valid JSON in the webhook body (use Raw Body, Content-Type: application/json).
- Missing/incorrect Authorization: include 'Authorization: Bearer '.
- Wrong endpoint/params: use the correct ChatGPT API path and model key.
- Unescaped or oversized fields: URL‑encode or truncate long form fields.
- Inspect Zapier task history to view the exact request/response and reproduce with curl.
If you want alternatives or deeper Zapier troubleshooting, see Zapier vs Make: Compare Zapier and Make