Uptime & Monitoring API

Distributed uptime & synthetic monitoring, one API call

Uptime, latency, DNS, SSL, content checks, incident alerts, and public status pages — create monitors over an API and track reachability with metered, pay-per-check access.

View example

Response surface

99.97%

Uptime 30d

142ms

Latency

http · dns · ssl

Checks

metered

Billing

Problem / audience

Outages, expired certs, and silent DNS changes surface to customers before they surface to you.

Agentry Sentinel watches the messy layer: HTTP status and latency, DNS resolution, SSL expiry, port reachability, and content keywords — with incident alerts and a public status page in one queryable API.

SaaS & web teams

Watch uptime, latency, and content drift across marketing sites, dashboards, and APIs from one surface.

Platform & SRE teams

Catch SSL expiry, DNS changes, and TCP/port failures before customers open tickets.

On-call & support

Route incident alerts to webhooks and publish public status pages instead of fielding status questions.

Try it

One request, a live monitor with uptime tracking.

POST /api/v1/sentinel/monitors

cURL request

curl -X POST \
  -H "Authorization: Bearer $AGENTRY_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "name": "Marketing site",
  "check_type": "https",
  "target": "https://example.com",
  "expected_status": 200,
  "keyword": "Welcome",
  "interval_seconds": 300,
  "timeout_seconds": 10,
  "failure_threshold": 2
}' \
  /api/v1/sentinel/monitors

JSON response (monitor list)

{
  "status": "ok",
  "total": 2,
  "generated_at": "2026-06-14T15:02:11Z",
  "monitors": [
    {
      "monitor_id": 4821,
      "name": "Marketing site",
      "check_type": "https",
      "target": "https://example.com",
      "interval_seconds": 300,
      "last_status": "up",
      "last_checked_at": "2026-06-14T15:01:54Z",
      "last_latency_ms": 142,
      "uptime_24h": 100,
      "uptime_30d": 99.97,
      "ssl_expires_at": "2026-09-02T00:00:00Z",
      "status_page_url": "https://status.agentry.systems/status/marketing-site"
    },
    {
      "monitor_id": 4822,
      "name": "API gateway",
      "check_type": "keyword",
      "target": "https://api.example.com/health",
      "interval_seconds": 60,
      "last_status": "degraded",
      "last_checked_at": "2026-06-14T15:01:58Z",
      "last_latency_ms": 871,
      "uptime_24h": 99.31,
      "uptime_30d": 99.62,
      "ssl_expires_at": "2026-08-19T00:00:00Z",
      "status_page_url": "https://status.agentry.systems/status/api-gateway"
    }
  ]
}

Website change detection

Know the moment a page changes — and see exactly what changed.

Turn on content-change tracking for any HTTP monitor. Sentinel snapshots the page, and when it changes you get a webhook alert plus a line-by-line diff — competitor pricing edits, policy updates, status changes, defacement. No extra service to wire up.

→ Baseline + change history with unified diffs
→ Webhook alerts on every change (and recovery)
→ Pairs with uptime, SSL-expiry, and latency-SLA checks

Example diff

@@ pricing page changed @@
- Pro plan — $49/mo
+ Pro plan — $59/mo
- 14-day free trial
+ 7-day free trial

Pricing

Starter and Scale, metered per check.

static fallback

Starter — 50 monitors

$0.009

/ check

Included checks100k requests/mo

Rate limit120/min

Burst20 / 10s

Scale — 500 monitors

$0.009

/ check

Included checks1M requests/mo

Rate limit600/min

Burst80 / 10s

How it works

From key to first monitor.

Get a key

Create scoped customer API access in the developer portal.

Subscribe to a plan

Choose Starter or Scale for metered Sentinel monitoring usage.

Create monitors

POST a target and check type; Sentinel runs the schedule and tracks uptime.

FAQ / trust

Built for production monitoring, not status theater.

Scoped API keys require sentinel.read and sentinel.write; usage is billed per check through the customer API ledger.

What can Sentinel monitor?

HTTP/HTTPS uptime and latency, DNS resolution, TCP ports, SSL certificate validity and expiry, and keyword/content checks against a target page.

Do I get public status pages?

Yes. Each monitor can publish a public status page at /status/{slug} with current state, recent incidents, and rolling uptime.

How do incident alerts work?

When a check crosses its failure_threshold, Sentinel opens an incident and fires a webhook payload you can route to chat, paging, or your own systems.

Where do checks run from?

Checks run from Agentry infrastructure today, with distributed multi-region vantage points on the roadmap so you can verify reachability from multiple locations.

Put uptime, SSL, and incident alerts behind your service.

Create an account, activate a Sentinel plan, and create your first monitor — all self-serve.