Quick Answer: Monitor API endpoints separately from your homepage by creating individual HTTP checks for each critical route (login, payments, /health), validating status codes and response bodies, setting per-endpoint timeouts based on normal latency, and routing alerts to the team that owns that service. Your homepage can return 200 while your API is broken.
Why does my homepage show "up" when my API is down?
Most teams start with one monitor on their marketing site or root URL. That check passes when the web server responds. It does not prove your application layer works.
Homepage checks and API checks answer different questions. A homepage monitor asks: "Can a browser load this page?" An API monitor asks: "Does this programmatic route return the correct response in acceptable time?" These fail independently.
Common scenarios where your homepage is green but your API is red:
- Your static landing page is served from a CDN while your API server is down
- A database connection pool is exhausted, breaking /api/v1/orders but not your marketing site
- A bad deploy broke the auth service while the frontend still loads
- Your API returns HTTP 200 with an empty error payload (a silent failure a homepage check never catches)
If your mobile app, partner integrations, or single-page application depends on API routes, monitoring only the homepage gives you false confidence. You need separate monitors for the endpoints that actually carry your product.
What should I validate on each API endpoint?
A status code check alone is the minimum bar, not the finish line. APIs fail in ways that still return 200.
Validate four things on every critical endpoint:
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HTTP status code. Expect 200 for healthy routes, 401 for auth-gated probes that use invalid credentials (to confirm the auth layer responds), or 204 for delete operations. Document the expected code per monitor.
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Response body content. Check for a required JSON field, a keyword, or a minimum payload size. An API that returns
{"error": "database unavailable"}with a 200 status is broken even though the HTTP layer succeeded. -
Response time. Set a latency threshold per endpoint. A login route that normally responds in 120ms and suddenly takes 4 seconds is degraded even if it eventually returns 200. Track latency trends, not just up/down.
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Authentication headers. Many API routes require Bearer tokens or API keys. Configure your monitor to send the same headers your clients use. Monitoring an authenticated endpoint without credentials tells you the route exists, not that authenticated requests work.
For a dedicated health route, go deeper. A /health or /healthz endpoint should verify database connectivity, cache availability, and downstream dependencies. Returning 200 unconditionally is worse than no health check at all because it trains your team to ignore alerts.
How do I set up separate API endpoint monitors step by step?
Step 1: List your critical API routes. Open your API docs or router config and identify endpoints where failure has customer impact. Typical starting set:
GET /healthorGET /api/healthPOST /api/v1/auth/loginPOST /api/v1/payments/processGET /api/v1/users/me(with a test auth token)
Do not try to monitor every route on day one. Cover the critical path first.
Step 2: Create one monitor per endpoint. Each monitor gets its own timeout, check interval, and alert channel. Lumping five endpoints into one check means one failure message and slower debugging.
In Overwatch, create an HTTP check for each route. Set the method (GET, POST, etc.), add auth headers if needed, and configure the expected status code.
Step 3: Tune timeouts from real data. Pull your 95th percentile response time from logs or APM for each endpoint. Set the monitor timeout to that value plus 30 to 50 percent buffer. A payment endpoint at p95 400ms should use a 600ms to 800ms timeout, not a global 5-second default.
Step 4: Add response body validation. For JSON APIs, check that the response contains a known field. For example, your health endpoint should include "status": "ok" and your user profile route should return a userId field. This catches silent failures where the server responds but returns garbage.
Step 5: Route alerts to the right team. API failures should page engineering, not marketing. Send payment API alerts to a high-priority Slack channel or PagerDuty rotation. Send lower-risk endpoint failures to a warnings channel. Test every alert destination monthly so you know messages actually arrive.
Step 6: Keep homepage and API monitors separate on your status page. If you publish a public status page, list API services as distinct components. Customers using your API care whether api.example.com works, not whether your marketing site loads.
How is API monitoring different from website uptime monitoring?
| Aspect | Homepage monitoring | API endpoint monitoring |
|---|---|---|
| What it checks | Page loads, static content | JSON responses, auth flows, data contracts |
| Typical timeout | 2 to 5 seconds | 200ms to 2 seconds (per endpoint) |
| Auth required | Usually no | Often yes (Bearer tokens, API keys) |
| Silent failures | Rare (page won't render) | Common (200 with error payload) |
| Who cares | Marketing, support | Engineering, mobile team, partners |
Both belong in your monitoring stack. The homepage tells you your public face is reachable. API monitors tell you your product actually works.
If you also run synthetic transaction tests (multi-step login flows, checkout sequences), treat those as a third layer on top of single-endpoint checks. Uptime monitors catch "is this route responding?" Synthetic tests catch "does the full user journey work?" Start with per-endpoint HTTP checks before adding complex scripted flows.
Frequently Asked Questions
Why is monitoring my homepage not enough for API health?
Your homepage is often a static page or a lightweight route served from cache. Critical API endpoints like login, payments, and search can fail independently due to database issues, auth service outages, or deploy bugs. A homepage returning 200 tells you nothing about whether those routes work.
What API endpoints should I monitor first?
Start with endpoints that directly affect revenue or authentication: login, signup, payment processing, and your /health or /status route. Add read-heavy routes like search and profile next. Skip low-risk internal admin routes until your critical path is covered.
What should a good API health check endpoint return?
A proper /health endpoint returns 200 only when core dependencies are reachable: database, cache, message queue, and any upstream service your API needs to function. Return 503 with a JSON body describing which dependency failed. Do not return 200 unconditionally.
How often should I check API endpoints?
Production APIs that handle user traffic should be checked every 30 to 60 seconds. Background or batch APIs can use 2 to 5 minute intervals. Match check frequency to how quickly you need to detect and respond to failures.
Can I use the same timeout for every API endpoint?
No. A login endpoint that normally responds in 80ms needs a different timeout than a report export that takes 8 seconds. Set per-monitor timeouts based on each endpoint's 95th percentile response time under normal load, plus a 30 to 50 percent buffer.
Your homepage going green is not proof your product works. Overwatch lets you monitor each API endpoint with its own HTTP check, timeout, and alert routing alongside your website, TLS, DNS, and cron job monitors. One dashboard, no blind spots. Get started free →