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API Request action error: legacy custom action has invalid JSON

Written by Owner

Updated at August 20th, 2025

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Table of Contents

Symptoms Causes How to fix it

Symptoms

After my legacy custom action was converted to an API Request action, you may encounter errors mentioning “invalid JSON.” This message can vary depending on the app’s API.

Causes

This happens when double quotes appear in the body of the request, causing the JSON to be invalid.

How to fix it

To fix this issue:

  • Go to your affected API Request action step.
  • Within the Body field:
    • Escape double quotes with a backslash before each one.
    • Or, if unnecessary, remove the double quotes entirely.

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