Glossary · APIs and integrations
Webhook
An event-driven HTTP message one system sends to another when something changes.
Definition
A webhook lets a provider notify another system instead of making the receiver check repeatedly. A repository can notify a build service after a push; a form service can notify an approved workflow after a submission. Receivers should verify authenticity, handle retries, and avoid logging sensitive payloads unnecessarily.
Why it matters
Webhooks can make automation timely and efficient, but they create an inbound endpoint that needs validation and monitoring.
Common misunderstanding
A webhook does not guarantee exactly-once delivery. Workflows must handle duplicate, delayed, or failed messages.
Related terms
Related system family: Secure Integrations & Custom Tools
Sources
- GitHub REST API documentation (opens in a new tab) · GitHub Docs
- HTTP (opens in a new tab) · MDN Web Docs
Last reviewed July 16, 2026