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Error Codes

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HTTP Status Codes

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Common Error Types

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Authentication Errors (401)

• Unauthorized - Missing or invalid API key
• Invalid API key - API key format is incorrect or expired

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Validation Errors (400)

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Missing Required Fields

• Missing required fields: from, to, and subject are required - Email sending
• Missing required fields: apiKey and to are required - Demo requests
• Missing required fields - General validation failure

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Invalid Formats

• Invalid email format - Email address doesn’t match expected pattern
• Invalid email format: [email] - Specific email address validation
• Invalid webhook URL format - Webhook URL validation failure
• Invalid scheduled_at - Date/time format is incorrect
• Invalid schedule time - Scheduled time is in the past or too far in future

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Configuration Errors

• Invalid endpoint type - Unsupported endpoint type specified
• Invalid configuration - Endpoint configuration validation failed
• Webhook URL is required - Missing webhook URL for webhook endpoints
• Forward-to email address is required - Missing email for forwarding endpoints
• Invalid forward-to email address format - Invalid forwarding email format

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Parameter Errors

• Invalid limit parameter - List limit must be 1-100
• Invalid offset parameter - Offset must be non-negative
• Invalid email ID provided - Email ID format is incorrect
• Invalid webhook format - Unsupported webhook payload format

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Resource Errors (404)

• Email not found - Email doesn’t exist or user lacks access
• Endpoint not found - Endpoint doesn’t exist or access denied
• Scheduled email not found - Scheduled email not found or unauthorized
• Original email not found - Cannot reply to non-existent email

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Rate Limiting (429)

• Rate limit exceeded - Too many requests (limit: 2 per second)
• Maximum 2 requests per second allowed. Upgrade or contact support for higher limits. - Rate limit details

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Server Errors (500)

• Failed to send email - Email sending operation failed
• Failed to schedule email - Email scheduling failed
• Failed to cancel scheduled email - Cancellation operation failed
• Failed to test endpoint - Endpoint testing failed
• Email sending limit reached. Please upgrade your plan to send more emails. - Account limits

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Error Response Format

{
  "error": "Error description",
  "message": "Additional context (optional)",
  "details": "Technical details (optional)"
}

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Rate Limit Headers