X-Accepted-GitHub-Permissions header for fine-grained permission actors

A new header will be sent back to API callers that use the fine-grained permission model (GitHub Apps and fine-grained PATs) to help developers discover which permissions are needed to call an API route. This new header, x-accepted-github-permissions, contains the list of permissions required to access the endpoint.

In the fine-grained permission model more than one permission may be needed to access an endpoint. Multiple sets of permissions may also be valid, since there are multiple ways to access data within GitHub. All valid sets are included in the header, each set separated by a semicolon (;).

For example, when calling "List project collaborators", you'll recieve the header x-accepted-github-permissions: repository_projects=write; organization_projects=admin. This indicates that to get the list of collaborators on a project, you need either the repository_projects Write permission or the organization_projects Admin permission.

This header is used in the same way as the x-accepted-oauth-scopes header for coarse-grained scope actors (OAuth apps and PATs (Classic)).

To learn more about troubleshooting permissions issues with GitHub Apps and fine-grained PATs and to get more information about this header, see "Insufficient permission errors". To see the permissions needed for each endpoint, see "Permissions required for GitHub Apps" and "Permissions required for fine-grained PATs".