# Glossary

Terms are listed alphabetically. Where a term has a name in the API, it is shown in `code`.

**Alert delay** - How long a failure must last before a particular contact is notified (`alertDelay`, in minutes).
Used to build [escalation](/alerts/escalation/) ladders.

**Alert subscription** - The link between a monitor and a contact that says which state changes (`up`, `down`,
`repeatedlyDown`) the contact is notified about. See [Subscriptions](/alerts/subscriptions/).

**API token** - A bearer credential you mint under **Integrations -> API**; it carries scopes, an expiry and an
optional IP allow-list. See [API authentication](/integrations/api-authentication/).

**Assertion** - A rule that checks part of a response (`status isOk`, `body contains "Checkout"`). All of a monitor's
assertions must pass. See the [assertion language](/reference/assert-language/).

**Attached sub-check** - An SSL expiry, domain expiry, DNSBL or Web Risk check that runs alongside an HTTP monitor
instead of as a separate monitor (`attached`).

**Band** - The status page tier your plan falls into, from the number of monitors it includes. See
[status page plan limits](/status-pages/plan-limits/).

**Check** - One run of a monitor's test from one location at one moment.

**Check log** - A monitor's recorded results (`GET /monitor/{id}/result`). Consecutive checks with the same outcome
are grouped into one row.

**Codename** - The short, stable name for why a check failed (`Timeout`, `DnsHostNotFound`, `Http 503`), in
`error.codename`. See [error codes](/reference/error-codes/).

**Component** - One row on a status page, backed by a monitor or set by hand (third-party).

**Confirmation** - The code a new email, SMS or voice contact must enter before it receives alerts.

**Contact** - A place alerts or reports go: an email address, phone number, messenger chat, webhook URL and so on
(`contact`).

**Contact group** - A named set of contacts, each with the events it receives, used to subscribe several contacts
to monitors at once.

**Cron schedule** - A cron expression that runs a monitor at set times instead of every N seconds
(`cronSchedule`).

**Down detection / recheck** - How HostTracker confirms a failure from other locations before recording a monitor as
down (`recheck.strategy`). See [down detection](/monitors/down-detection/).

**Error budget** - The downtime an SLA target allows over a period; 99.9% over 30 days is about 43 minutes.

**Fallback** - What happens when no location in a monitor's pools is available: `geo`, `world` or `starve`.

**Full log** - A monitor option that logs checks in 5-minute groups instead of 60-minute groups (`fullLog`).

**Idempotency key** - A header (`Idempotency-Key`) that makes a retried API write return the first result instead of
running twice.

**Incident** - A confirmed down episode of a monitor, from the confirmed failure to the confirmed recovery. See
[What is an incident](/incidents/what-is-an-incident/). Not the same as a status page incident.

**Instant check** - A one-off check you run now, outside any monitor's schedule (`POST /check`). See
[Instant checks vs monitors](/getting-started/instant-checks-vs-monitors/).

**Interval** - How often a monitor runs, in seconds in the API (`interval`).

**Job** - An asynchronous API operation (bulk create, report generation) you poll with `GET /job/{id}`.

**Location (agent, checkpoint)** - One monitoring vantage point with a country and city (`GET /agent`).

**Maintenance window** - A scheduled period in which chosen monitors hold back alerts and/or statistics. See
[maintenance](/maintenance/overview/).

**MCP** - The Model Context Protocol; HostTracker's MCP server lets AI assistants operate your account. See
[MCP](/integrations/mcp/).

**Monitor** - A configured, recurring check of one target, with a type, schedule, locations and subscriptions
(`monitor`).

**Monitor state** - `up`, `down`, `paused` or `maintenance`.

**Package (plan)** - Your subscription tier; it sets your limits. See [plan limits](/reference/plan-limits/).

**Pool** - A named group of locations (a region, or `allworld` for everywhere) used to choose where a monitor runs.

**Public statistics** - An option that makes a monitor's statistics viewable without signing in (`openStat`).

**Report subscription** - The link between a monitor and an email contact that receives scheduled uptime reports
(`daily` to `yearly`).

**Scope** - What an API token may do, per area (`monitor:read`, `contact:write`, ...).

**Severity** - An incident's size by duration: `minor` (under 5 min), `major` (5-60 min), `critical` (1 hour or
more).

**SLA target** - The uptime percentage you commit to (`slaTarget`). See [Uptime and SLA](/incidents/uptime-sla/).

**Slug** - The permanent part of a status page's address: `status.host-tracker.com/<slug>`.

**Snapshot** - What a failing check received: an HTTP response or a browser screenshot. See
[snapshots](/incidents/snapshots/).

**Status page** - A public (or password-protected) page showing your services' status to your users. See
[status pages](/status-pages/overview/).

**Status page incident** - An announcement you declare on a status page, with a timeline of updates, sent to its
subscribers.

**Subaccount** - A separate login with limited rights on your account. See [subaccounts](/account/subaccounts/).

**Subscriber** - Someone (email) or something (Slack, Teams, webhook) that receives a status page's announcements.

**Tag** - A free-form label on a monitor, used to filter and to target bulk edits and webhooks.

**Third-party component** - A status page row for a service you do not monitor, whose state you set by hand.

**Uptime** - The share of measured time a monitor was up over a period, excluding downtime inside maintenance
windows that suppress statistics.

**Webhook** - A signed HTTPS delivery of HostTracker events to your endpoint (`webhook`). See
[webhooks](/integrations/webhooks/).

**Webhook contact** - An alert contact of type `http` that posts monitor alerts to a URL, with an optional custom
payload. Not signed; different from a v2 webhook.

## Related

- [Monitor settings reference](/reference/monitor-settings/)
- [Error codes reference](/reference/error-codes/)
- [Monitoring locations reference](/reference/locations/)