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Errors & Status Codes

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Overview

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Error Response Format

{
  "error": "Missing required parameter",
  "message": "Either polymarket_market_slug or kalshi_market_ticker is required"
}

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HTTP Status Codes

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Common Errors

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400 Bad Request

• Missing required parameters
• Invalid parameter values
• Malformed JSON in request body

• Check API documentation for required parameters
• Validate parameter types and formats
• Verify JSON syntax

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401 Unauthorized

• Missing x-api-key header
• Invalid API key
• Expired API key

• Include x-api-key: YOUR_API_KEY header in all requests
• Verify API key is correct
• Request new API key if expired (contact team@predexon.com)

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403 Forbidden

• API key lacks required permissions
• Account suspended

• Check account permissions
• Contact support for access issues

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404 Not Found

• Invalid market slug or ticker (e.g., polymarket_market_slug, kalshi_market_ticker)
• Invalid token ID or condition ID
• Resource has been deleted or market is no longer available
• Incorrect endpoint URL

• Verify market identifiers (slugs, tickers) are correct
• Check if market still exists on the source platform
• Confirm endpoint URL is correct (base URL: https://api.predexon.com/v1)

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422 Unprocessable Entity

• Incompatible parameter combinations (e.g., both polymarket_market_slug and kalshi_market_ticker provided)
• Invalid confidence threshold values
• Time range validation failures (start_time >= end_time)
• Business logic validation failure

• Review parameter constraints in endpoint documentation
• Ensure only one of mutually exclusive parameters is provided
• Check example requests in documentation
• Verify time ranges are valid (start_time < end_time)

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429 Too Many Requests

• Exceeded rate limit (100 requests/minute per API key)

• Implement exponential backoff
• Reduce request frequency
• Use batch endpoints when available (e.g., /matching-markets/batch)
• Consider caching responses
• Contact team@predexon.com for higher rate limits

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500/502/503 Server Errors

• Temporary service issues
• Upstream dependencies unavailable

• Retry with exponential backoff
• Check status page
• Contact support if persistent

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Error Handling Best Practices

1. Parse error response: Always read the detail field for specific error information
2. Implement retries: Use exponential backoff for 429, 500, 502, 503 errors
3. Log errors: Include instance field for debugging
4. Validate before sending: Client-side validation reduces 400/422 errors

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