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CI/CD pipelines depend on GitHub webhooks like push, pull_request, and workflow_run. GitHub does not retry failed webhook deliveries and sends no failure notification — so a broken CI trigger can go undetected for hours. Webhook Guardian monitors GitHub webhook delivery logs every 5 minutes and alerts your team via Slack the moment a delivery fails, with the delivery UUID and a one-click redeliver link.

GitHub Webhook Monitoring for CI/CD Pipelines

Q: What happens when a push webhook fails in CI?

If the push webhook fails to deliver, your CI system never receives the trigger event. Builds do not run, tests are not executed, and deployment pipelines do not start. The team continues pushing code assuming CI is running, discovering the outage only when someone notices that nothing has built or deployed.

May 20, 2026 · GitHub monitoring

Your CI pipeline stopped running. Every push for the last four hours went nowhere — no builds, no tests, no deployments. The GitHub webhook is still configured, still showing as active, still passing its ping. But the push deliveries have been failing silently, and GitHub never told you.

This is the default GitHub behavior. It logs failures. It does not alert on them.

Which GitHub Webhooks Power CI/CD Pipelines?

Modern CI/CD pipelines are built almost entirely on GitHub webhook events. The events that matter most:

Event	What it drives
`push`	CI trigger (tests, lint, build), code sync to staging
`pull_request`	Automated review bots, status checks, label workflows
`workflow_run`	Downstream automation after CI completes
`deployment` / `deployment_status`	Environment tracking, release systems
`create` / `delete`	Branch lifecycle events, branch protection automations

Every event in this table is a potential single point of failure. If the delivery fails, the downstream system never learns the event occurred.

What Happens When a GitHub Push Webhook Fails?

When a push event fails to deliver:

Your CI system (Jenkins, CircleCI, Buildkite, or a GitHub Actions external trigger) never receives the event.
No build starts. No tests run. No build status is reported back to the PR.
Deployments that depend on a passing CI run never trigger.
Engineers continue pushing code. They assume CI is running because there are no error messages — just silence.
Someone notices hours later when they check why a PR has no status checks, or when a deploy that should have happened hasn't.

For pull_request webhooks, the impact is different but equally disruptive: automated review bots stop commenting, required status checks never appear, and reviewers cannot merge even when the code is ready.

Does GitHub Retry Failed Webhook Deliveries?

No. This is the key difference between GitHub and Stripe or Shopify. GitHub makes one delivery attempt per event. If that attempt fails — your endpoint returns a non-2xx response, times out after 10 seconds, or is unreachable — GitHub records the failure in the delivery log and stops. There are no automatic retries.

You can manually redeliver a failed event from the delivery log (Settings → Webhooks → [webhook] → Recent Deliveries → Redeliver), but you have to know the failure happened first. GitHub's delivery log retains records for 72 hours — after that, the record is gone.

How Do You Monitor GitHub Webhook Failures in Your CI/CD Pipeline?

The GitHub REST API exposes the same delivery history that the dashboard shows:

# List deliveries for a repository webhook
GET /repos/{owner}/{repo}/hooks/{hook_id}/deliveries
Authorization: Bearer {token}

# Filter by status to find failures
# Each delivery object includes:
# redelivery: false
# status: "failed"
# status_code: 500
# event: "push"
# guid: "12a3b4c5-..."

You can build a poller yourself: fetch deliveries every 5 minutes, filter for status: "failed", de-duplicate events you've already seen, and fire a Slack alert. Or use Webhook Guardian, which does this for every connected repository and organization webhook without any infrastructure to maintain.

What Does a GitHub Webhook Failure Alert Look Like?

When Webhook Guardian detects a failed delivery, it sends a Slack alert structured as:

⚠️ GitHub webhook delivery failed

Event:       push
Repository:  your-org/your-repo
Delivery ID: 12a3b4c5-6d7e-8f90-ab12-cd34ef567890
Status:      500 Internal Server Error
Failed at:   2026-05-20 14:32:07 UTC

[Redeliver →]  [View in GitHub →]

The delivery UUID lets you look up the exact payload in GitHub's delivery log, and the redeliver link triggers a new delivery attempt without leaving the alert. For most CI failures, redelivering the event is all you need to do — the pipeline picks it up and runs normally.

FAQ: GitHub Webhook Monitoring for CI/CD

Does GitHub notify you when a webhook delivery fails?

No. GitHub records failed deliveries in the webhook delivery log but sends no alert or notification when a failure occurs. You have to check the delivery log manually or use a monitoring tool that polls the GitHub API automatically.

What happens when a push webhook fails in CI?

CI never runs. No builds start, no tests execute, and no deployment pipelines trigger. Engineers keep pushing code assuming the pipeline is working, discovering the failure only when they notice builds haven't run or a deploy hasn't happened.

How do I monitor GitHub webhook failures for CI/CD?

Connect your GitHub account to Webhook Guardian via read-only OAuth. Webhook Guardian polls the GitHub delivery log every 5 minutes. When a delivery fails, you receive a Slack alert with the event type, delivery UUID, status code, and a one-click redeliver link.

Stop finding out about broken CI triggers from your team. Connect GitHub to Webhook Guardian and get alerted within 5 minutes when any push, pull_request, or deployment webhook fails to deliver. Start free for 14 days →

Also see: GitHub Webhook Delivery Logs: What They Show and What They Miss · How Webhook Guardian works