To configure Azure Active Directory (Microsoft Entra ID) as the Identity Provider (IdP) for a GitHub organization, you must define the Service Provider (GitHub) details in the Azure portal.

• Identifier (Entity ID): This uniquely identifies the application for which single sign-on is being configured. According to Microsoft documentation, the pattern for a GitHub organization is https://github.com/orgs/<Organization_ID>.
• Reply URL (Assertion Consumer Service URL): This is the endpoint where the IdP sends the SAML authentication response. GitHub listens for these responses at the saml/consume endpoint relative to the organization URL: https://github.com/orgs/<Organization_ID>/saml/consume.
• Sign on URL: This is the URL where users go to sign in to the application. For GitHub organizations, this is simply the organization's landing page: https://github.com/orgs/<Organization_ID>.

Microsoft Learn. (2024). Tutorial: Azure Active Directory single sign-on (SSO) integration with a GitHub Enterprise Cloud Organization. Retrieved from https://learn.microsoft.com/en-us/entra/identity/saas-apps/github-tutorial

Relevant Section: "Basic SAML Configuration" steps. It explicitly lists the patterns:

Identifier (Entity ID): https://github.com/orgs/

Reply URL: https://github.com/orgs//saml/consume

Sign on URL: https://github.com/orgs/

GitHub Docs. (n.d.). Configuring SAML single sign-on for your enterprise. Retrieved from https://docs.github.com/en/enterprise-cloud@latest/admin/identity-and-access-management/using-saml-for-enterprise-iam/configuring-saml-single-sign-on-for-your-enterprise

Relevant Section: Confirms the assertion consumer service (ACS) URL format ends in /saml/consume.