Introduction
Learn how Varen monitors your API dependencies and alerts you before breaking changes hit production.
Varen watches the APIs your product depends on — Stripe, OpenAI, AWS, and 100+ more — and tells you when something changes. Not just that it changed, but what changed, why it matters, and how to fix it.
Why Varen?
External API changes are the #1 cause of silent production failures. A provider deprecates a field, renames a parameter, or changes a response format — and your integration breaks without warning.
Varen solves this by:
- Monitoring API documentation continuously for changes
- Classifying every change by severity (breaking, deprecated, cosmetic, etc.)
- Alerting you instantly for critical changes, with a daily summary for the rest
- Providing actionable context — diffs, migration guides, and suggested fixes
How it works
- Pick APIs to monitor — choose from 100+ pre-configured catalog APIs, or add any custom API by pasting its documentation URL
- Varen scans continuously — Hobby plans check every 24 hours, Pro plans check every hour
- Changes are detected and classified — using deterministic OpenAPI diffing for structured specs, and AI-powered analysis for unstructured docs
- You get alerted — breaking changes trigger instant email/Slack alerts (Pro), everything else goes into a daily summary
Key concepts
| Concept | Description |
|---|---|
| Monitor | An API you're tracking. Can be a catalog API or a custom URL. |
| Change | A detected modification to an API's documentation or spec. |
| Severity | How impactful a change is: Breaking, Deprecated, Removed, Added, Changed, Fixed, or Cosmetic. |
| Health Score | A 0–100 stability rating for each API, updated daily based on change frequency and severity. |
| Snapshot | A point-in-time capture of an API's documentation, used to compute diffs. |