API Monitoring

Your API is your product. Monitor REST APIs, GraphQL endpoints, and webhooks to ensure they're fast, reliable, and meeting SLA commitments.

APIs power modern applications. When your API fails or slows down, it's not just your app that breaks—it's every customer, partner, and integration that depends on you.

Why API monitoring matters

SLA compliance

Many APIs have uptime commitments in their SLAs. Without monitoring, you won't know if you're meeting your 99.9% uptime promise until customers complain.

Performance visibility

API response times directly impact user experience. A slow API feels broken even when it's technically "up." Track response times to catch degradation early.

Dependency awareness

Your API likely depends on databases, caches, third-party services, and more. Monitoring helps you understand which dependency failures cause customer-facing issues.

Faster incident response

Get alerted to API issues immediately rather than waiting for support tickets. The faster you know, the faster you can fix it.

What to monitor in your API

Health check endpoint

Every API should have a /health or /status endpoint that verifies internal dependencies.

  • Database connectivity
  • Cache availability
  • External service status

Critical business endpoints

  • Authentication – Login, token refresh, OAuth flows
  • Core functionality – Whatever your API does most
  • Payments – If you process payments, monitor those endpoints closely
  • Webhooks – Verify outgoing webhook delivery

API monitoring best practices

Monitor more than status codes

A 200 OK doesn't mean success. Use keyword monitoring to verify response content. An endpoint returning {"error": "database_timeout"} with status 200 is still broken.

Track response times

Set response time thresholds. If your API normally responds in 100ms and suddenly takes 2 seconds, that's worth investigating even if it's still "up."

Monitor from multiple regions

If your API serves a global audience, check from multiple geographic locations. CDN issues, regional outages, and DNS problems can affect some users but not others.

Test authenticated endpoints

Include API keys or authentication headers in your monitors. A public health check might pass while authenticated endpoints fail due to auth service issues.

Monitoring different API types

REST APIs

Monitor GET endpoints directly. For POST/PUT endpoints, use a dedicated test endpoint or monitor the health check that verifies those paths work.

GraphQL APIs

Monitor the GraphQL endpoint with a simple query. Verify the response contains expected data rather than GraphQL errors.

Webhooks

Use heartbeat monitoring for outgoing webhooks. Have your webhook handler ping UpDog when it receives and processes events successfully.

Example: API health check

# A good health check endpoint verifies dependencies
GET /health HTTP/1.1
Host: api.example.com

Response:
{
  "status": "healthy",
  "database": "connected",
  "cache": "connected",
  "stripe": "reachable",
  "response_time_ms": 45
}

Configure UpDog to check this endpoint and verify the response contains "status": "healthy".

FAQ

Start with your health check endpoint, then add critical business endpoints. Monitor response status codes, response times, and optionally verify response content.

For production APIs, every 1-3 minutes. For critical payment or auth endpoints, every 1 minute. Less critical internal APIs can use 5-15 minute intervals.

Yes. You can include API keys, Bearer tokens, or custom headers in your monitoring requests to test authenticated endpoints.

Related resources

Monitor your API

Know when your API fails before customers report it. Fast alerts, response time tracking, SLA visibility.

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  • 1-minute check intervals
  • Response time tracking
  • Content verification
  • Custom headers support