GitHub webhook trigger context
When a workflow is automatically triggered by a GitHub Webhook, metadata from the triggering GitHub event is automatically generated as context. This article describes the context fields passed for each event.
How context works
When a workflow is triggered by a GitHub Webhook, the system extracts metadata from the event payload and structures it as trigger context. This context is automatically appended to the system prompt of AI Agent Blocks in the workflow, so the AI can reference the trigger metadata without any explicit configuration.
Fields common to all events
These fields are always passed for every GitHub Webhook event.
event
The type of event that triggered the workflow
push, pull_request, release
repository
The full name of the repository
owner/repo-name
branch
The base branch name
main, release/v2
sender
The login name of the user who triggered the event
username
All field values are passed as strings. Numeric values (such as PR numbers) are also passed as strings.
Event-specific fields
Push
Additional fields passed when code is pushed to a branch.
commitSha
The SHA of the HEAD commit
abc123def456...
commitMessage
The message of the HEAD commit
Fix: update login process
commitUrl
The URL of the HEAD commit
https://github.com/owner/repo/commit/abc123
commitCount
The number of commits included in the push
3
Pull request
Additional fields passed when a pull request is opened, updated, or closed.
action
The action performed on the PR
opened, closed, synchronize
prNumber
The PR number
42
prTitle
The title of the PR
Feature: new dashboard
prUrl
The URL of the PR
https://github.com/owner/repo/pull/42
headBranch
The source branch of the PR
feature/new-dashboard
baseBranch
The target branch of the PR
main
headSha
The HEAD commit SHA of the PR
def456abc123...
merged
Whether the PR has been merged
true, false
Release
Additional fields passed when a new release is published.
action
The action performed on the release
published, created, edited
tagName
The tag name of the release
v1.2.3
releaseName
The name of the release
Version 1.2.3
releaseUrl
The URL of the release
https://github.com/owner/repo/releases/tag/v1.2.3
prerelease
Whether the release is a pre-release
true, false
How to reference context
Trigger context is automatically appended to the system prompt of AI Agent Blocks in the following format.
By simply writing "Summarize the commit message" in the AI Agent Block prompt, the AI can automatically reference the commit information from the context.
Related pages
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