Events
Events are your product analytics — the things users do in your app. Page views, signups, purchases, feature toggles. If you’ve used Mixpanel, Segment, or PostHog, this works the same way.plan” or “daily active users by country.”
Within the events protocol, there are several message types:
| Type | What it does |
|---|---|
| track | Record a user action — page_view, sign_up, purchase |
| identify | Link a device to a known user ID when they log in |
| session | Device and session context (SDKs send this automatically) |
| group | Associate a user with a company or team |
| revenue | Track a purchase with amount, currency, and order ID |
| alias | Merge two user identities across devices |
track and identify. Sessions are managed automatically by the SDK — when a user opens your app, a session starts and groups all their events together. The rest are for specific use cases.
Read more: Events & Properties | Users & Identity | Sessions
Logs
Logs are your application’s internal voice — errors, warnings, debug info. Tell is a full structured logging framework with 9 severity levels, service tags, and arbitrary metadata.Snapshots
Snapshots pull data from services outside your app on a schedule. You configure a connector, and Tell reaches out to APIs like GitHub or Shopify to capture metrics over time.Properties
Properties are the key-value pairs attached to events and logs. They’re what make your data queryable.- Event properties:
plan,amount,source,page_url - User traits:
email,company,signup_date(set viaidentify) - Log fields:
service,level,error_code
The pipeline
When data arrives — from an SDK, an HTTP request, or a connector — it passes through a pipeline before being stored. The pipeline routes data to the right destination, and optionally filters, redacts PII, or transforms it in flight. For most setups you don’t need to configure this. The defaults work. When you need more control — routing logs to disk and events to ClickHouse, redacting emails before storage, filtering out health checks — the pipeline is fully configurable. Read more: Pipeline OverviewWhat’s next
- Quickstart — send your first event in under 5 minutes
- What to Track — choosing between events, logs, and snapshots
- SDKs — language-specific integration guides