Fix: CodeBuild GitHub Actions Webhook Not Triggering a Build
When the CodeBuild webhook does not start a build, GitHub already holds the answer in the delivery Response. Here is the AWS-documented way to read it.
According to AWS CodeBuild docs, if your CodeBuild-hosted runner webhook is not working or the job hangs, the WORKFLOW_JOB_QUEUED event may be failing to trigger a build. GitHub records CodeBuild response for each delivery, so you can read the exact error. This page walks the AWS-documented debug steps.
Confirm the event is enabled
According to AWS docs, open https://github.com/<user>/<repo>/settings/hooks, choose Edit on the CodeBuild webhook, and confirm it is enabled to deliver Workflow jobs events. If that event is off, no build is ever triggered.
Read the delivery Response
According to AWS docs, go to the Recent Deliveries tab, find the corresponding workflow_job.queued event, and expand it. Review the labels field in the Payload to confirm it matches your project, then open the Response tab, which contains the response or error message returned from CodeBuild.
Add a WORKFLOW_NAME filter if needed
According to AWS docs, when using the WORKFLOW_JOB_QUEUED event you may need to add a WORKFLOW_NAME filter to your webhook filter group, using a regular expression that matches the workflow name, so only the intended workflows trigger builds.
Debug via the GitHub API
According to AWS docs, you can also inspect deliveries with the GitHub REST API: list deliveries for the repository webhook, note the delivery ID, then fetch that delivery; CodeBuild reply appears in the response section of the payload.
Rule out the label
According to AWS docs, if the payload labels look wrong, the runs-on label may not match your project. Confirm the codebuild-<project>-${{ github.run_id }}-${{ github.run_attempt }} format and exact project name before digging further into the webhook.