🔑

API Key Tester

Backend: Checking

Documentation

How It Works

  1. Select an AI provider (e.g., OpenAI, Anthropic, Google Gemini).
  2. Choose a model from the list or enter a custom model name.
  3. Enter your API key for the selected provider.
  4. Click "Test API Key" to validate and view the result instantly.

Tip: Use scoped or test keys whenever possible.

Supported Providers

  • OpenAI (GPT-4, GPT-3.5)
  • Anthropic (Claude)
  • Google Gemini
  • Cohere
  • Hugging Face
  • Replicate
  • Custom Providers

Best Practices

  • Never share your production secrets publicly.
  • Rotate your API keys regularly.
  • Review provider quotas and permissions.
  • Prefer least-privilege keys for testing.

Troubleshooting

  • Invalid key: Ensure the key matches the provider format and has access permissions.
  • Model not found: Double-check the model ID and availability in your region/account.
  • Rate limiting: Wait a few minutes and try again.

Error Reference Guide

Authentication Errors

401 Unauthorized

Cause: Invalid or expired API key

Solution: Verify your API key is correct and hasn't been revoked. Generate a new key from your provider's dashboard if needed.

403 Forbidden

Cause: API key lacks necessary permissions or account restrictions

Solution: Check your API key permissions in the provider dashboard. Ensure your account has access to the requested model.

Model & Request Errors

404 Not Found

Cause: Model name doesn't exist or isn't available for your account

Solution: Verify the model name spelling. Check if the model requires special access or is region-specific.

400 Bad Request

Cause: Invalid request format or missing required parameters

Solution: Ensure all required fields are filled. Check that provider and model names are properly formatted.

Rate Limiting & Quota Errors

429 Too Many Requests

Cause: Exceeded rate limits for the API

Solution: Wait before making another request. Consider upgrading your plan for higher rate limits.

402 Payment Required

Cause: Insufficient credits or quota exceeded

Solution: Check your billing status and add credits or upgrade your plan.

Server & Network Errors

500 Internal Server Error

Cause: Provider's server encountered an error

Solution: Wait a few moments and retry. Check the provider's status page for ongoing incidents.

503 Service Unavailable

Cause: Service is temporarily unavailable or under maintenance

Solution: Check the provider's status page. Try again later.

Network Error / Timeout

Cause: Connection issues or request timeout

Solution: Check your internet connection. Verify the API endpoint is accessible from your network.

Provider-Specific Errors

OpenAI

• Key format: sk-...

• Common issue: Organization ID mismatch - ensure key belongs to correct org

Anthropic (Claude)

• Key format: sk-ant-...

• Common issue: Model version availability - some models may be in beta

Google Gemini

• Common issue: API must be enabled in Google Cloud Console

• Check: Gemini API is enabled for your project

Cohere

• Common issue: Model access tier restrictions

• Verify: Your plan includes access to the selected model

💡 General Tips

  • Always check the error message details for specific guidance
  • Keep your API keys secure and never share them publicly
  • Monitor your usage and billing to avoid unexpected charges
  • Test with smaller/cheaper models first before using production models
  • Check provider documentation for model-specific requirements

Security Best Practices

  • Never commit API keys to version control systems
  • Use environment variables for storing sensitive keys in production
  • Rotate keys regularly (at least every 90 days)
  • Set up usage alerts to detect unusual activity
  • Use scoped/restricted keys with minimal permissions for testing
  • Monitor API logs for unauthorized access attempts

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