GitHub App installation access tokens are the recommended method for CI/CD and other automations. They are generated for a specific installation of a GitHub App on a repository or organization. This model provides significant security advantages because the app has its own identity, separate from any user account. Most importantly, GitHub Apps are designed with a fine-grained permission model, allowing administrators to grant only the precise permissions required for the app to perform its function (e.g., read-only access to code, write access to issues), adhering to the principle of least privilege.

A. Personal Access Tokens (PATs): While fine-grained PATs exist, they are tied to a user account. If the user leaves the organization or their permissions change, the automation breaks, making them less robust and not the recommended choice for organizational CI/CD.

C. Device Tokens: These are used for the device authorization flow, which is an interactive process for headless applications (like a CLI) to obtain an OAuth token on behalf of a user. They are not intended for non-interactive CI/CD automation.

D. OAuth tokens: Standard OAuth tokens are generated for a user authorizing an application. They are tied to the user's identity and permissions and typically use broad scopes, lacking the fine-grained control inherent to GitHub Apps.

1. GitHub Docs

"About creating GitHub Apps." This document explicitly states

"GitHub Apps are the officially recommended way to integrate with GitHub because they offer much more granular permissions to access data... For CI/CD

you can use a GitHub App to run workflows." It contrasts this with OAuth Apps and PATs. (Source: GitHub

Inc.

Official Documentation

Developers > Apps > Building GitHub Apps > About building GitHub Apps).

2. GitHub Docs

"Choosing an authentication method." This guide recommends GitHub Apps for system-to-system interactions

such as CI/CD. It highlights that "GitHub Apps have granular permissions and use short-lived tokens

which reduces the risk of leaked credentials." (Source: GitHub

Inc.

Official Documentation

Developers > Apps > Building apps > Choosing an authentication method).

3. GitHub Docs

"Managing your personal access tokens." In the section on choosing the right token

the documentation advises

"For automations that will interact with repositories in an organization

you should use a GitHub App. GitHub Apps have more granular permissions and are not associated with a user account." (Source: GitHub

Inc.

Official Documentation

Authentication > Keeping your account and data secure > Managing your personal access tokens).