Sentinel
Sentinel monitors websites and infrastructure from outside the services it tracks, checking them across multiple regions.
What Sentinel is
Sentinel monitors websites and infrastructure from outside the services it tracks, checking them across multiple regions. Its checks cover uptime, SSL certificates, DNS records, domain expiry, page keywords, JSON and API responses, ping, TCP ports, and heartbeat or cron jobs. Checks can run from four regions as frequently as every 30 seconds, with regional agreement used before an outage is flagged. Alerts can be sent by email, SMS, Slack, Discord, Telegram, Microsoft Teams, or webhooks. Sentinel also provides customizable status pages and incident history, with limits that depend on the plan, and its integrations include GitHub, Terraform, PagerDuty, command-line access, and MCP connections for compatible AI agents. The Free plan includes up to 10 monitors, five-minute checks, and one public status page. A downloadable macOS menu bar app requires macOS 13.0 or later and a read-only API token.
Good
- Checks services from four regions.
- Tracks uptime, certificates, DNS, APIs, ports, and more.
- Alerts include email, SMS, chat apps, and webhooks.
- Free plan includes up to 10 monitors.
- MCP connects compatible agents to monitors.
Watch out
- Free checks run every five minutes.
- Free plan includes one public status page.
- macOS app requires macOS 13.0 or later.
Who it suits
Sentinel suits digital agencies, freelance developers and designers, and SaaS teams that manage one or more sites. It offers monitoring, status pages, and incident history for those services.
Verdict
Sentinel combines multi-region monitoring with a broad set of checks, alert channels, and status-page features. Check the plan limits and macOS app requirements against your setup before choosing it.
Plans and prices
From Sentinel's own pricing page, checked 15 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Free | Free | up to 10 monitors · 5-minute checks · uptime, SSL, DNS, domain, keyword, ping, port, JSON/API and server-error checks · 1 public status page · email, Discord and Telegram alerts · API, CLI, Terraform, MCP · macOS app |
| Starter | $14 a month | up to 25 monitors · 1-minute checks · heartbeat/cron monitoring · Slack and Teams alerts · US/Canada SMS · 5 client status pages · Billed monthly |
| Pro | $29 a month | up to 100 monitors · Lighthouse audits · signed webhooks · one team with up to 5 members · 10 branded status pages · custom-domain status pages · Billed monthly |
| Business | $79 a month | up to 300 monitors · 30-second checks · PagerDuty · unlimited teams and members · unlimited status pages · client-ready uptime reports · priority support · Billed monthly |
The facts
Each one read from Sentinel's own pages, with the date it was checked.
What it does
- AI access
- The MCP integration connects Claude, ChatGPT, and other MCP-compatible agents to monitors for questions and incident triage.checked 7 Oct 2026
- Alerts
- Alert channels include email, SMS, Slack, Discord, Telegram, Microsoft Teams, and webhooks.checked 7 Oct 2026
- API authentication and limits
- API calls use bearer tokens, and standard requests are limited to 120 per minute with no daily or monthly quota.checked 15 Oct 2026
- API base and versioning
- The REST API uses https://sentinel.rootstuff.io/api/v1 and promises additive-only changes within version 1.checked 15 Oct 2026
- API monitoring
- Custom HTTP requests can assert JSON response paths and values to detect silent API failures.checked 15 Oct 2026
- Checks
- It monitors uptime, SSL certificates, DNS records, domain expiry, page keywords, JSON/API responses, ping, TCP ports, and heartbeat or cron jobs.checked 7 Oct 2026
- CLI
- The CLI is installed with npm, requires Node.js 18 or newer, supports CI/CD workflows and manages monitors, incidents, teams, webhooks and status pages.checked 15 Oct 2026
- Data retention
- Terms state that monitoring data is retained for 30 days on Free, 90 days on Pro and one year on Business.checked 15 Oct 2026
- DNS monitoring
- Sentinel watches seven DNS record types and alerts when records change.checked 15 Oct 2026
- Documentation depth
- Documentation includes getting-started guides, monitor concepts, integrations, CLI instructions, API references, pagination, errors, rate limits and troubleshooting.checked 15 Oct 2026
- Founder and location
- Adam Balée identifies himself as Sentinel’s founder and developer, and says Rootstuff is based in West Chester, Pennsylvania.checked 7 Oct 2026
- Heartbeat and cron
- Push heartbeat and cron monitors open incidents when expected job pings are missing or report failure.checked 15 Oct 2026
- Hosted service
- The MCP server documentation describes Sentinel as a hosted service and says its server code is not open source.checked 15 Oct 2026
- Integrations
- GitHub deploy markers, Terraform, PagerDuty, a CLI and MCP-based AI assistants are supported; Zapier and Datadog are listed as coming soon.checked 15 Oct 2026
- Keyword monitoring
- Keyword checks verify required page text or detect unwanted error and defacement content.checked 15 Oct 2026
- Licence
- The hosted Sentinel service is proprietary, while the published Sentinel CLI is open source under the MIT licence.checked 15 Oct 2026
- Limit: availability guarantee
- Terms say Rootstuff strives for 99.9% uptime but does not guarantee uninterrupted service and is not liable for missed incidents or monitoring delays.checked 15 Oct 2026
- Limit: compliance
- Slack's security listing says the app is not HIPAA compliant, does not support SAML, has no dedicated security team, no vulnerability disclosure program and no bug bounty.checked 15 Oct 2026
- Limit: webhook tier
- Custom webhooks are documented as a Pro and Business feature, so they are unavailable on Free and Starter.checked 15 Oct 2026
The company
- Company stack
- Rootstuff's case study says Sentinel is built with Laravel, Vue and Inertia and operates checks from multiple regions.checked 15 Oct 2026
- Founded
- The company timeline says Sentinel was founded in 2024 and launched in February 2026.checked 7 Oct 2026
Where it runs
- Desktop app
- Sentinel offers a downloadable macOS menu bar app that requires macOS 13.0 or later and a read-only API token.checked 7 Oct 2026
- Limit: macOS desktop coverage
- The maker's blog states that the menu-bar app is macOS-only, with no Windows or Linux build at that time.checked 15 Oct 2026
- macOS app
- The free menu-bar app is version 1.0.5, requires macOS 13 or later, uses a read-only API token and refreshes from 15 seconds to five minutes.checked 15 Oct 2026
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