GraphQL API cannot assigned an issue to copilot using a different branch than default

[Kreestyan]

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Hi,
We really appreciate the guide provided here to assign an issue to copilot using GraphQL API, however this API is not able to direct copilot using a different branch than default one. Although as explain in this response, one can easily do so from the UI.

I understand we can pre-assign a new branch to an issue, and then eventually re-assign it to copilot but when doing so, the agent is still starting branching out of the default branch. It is not considering the associated branch created earlier.
I also tried to add directions to request the agent to create a branch from stage but it cannot work as, it seems the branch is created 1st and only then the agent starts reading the instruction, so at that point it i snow too late.

Ideally, it would be nice to enhance that GraphQL API to add parameters consistent with what can be done with the UI (e.g. pick a ref branch and/or assign its own agent).

Is there any plan with that respect or am I missing a feature that would allow assigning my issue to copilot so that it start working out of my desired branch when specified - instead of always default? Note that my organization has granted ability to change default branch only to organization owner therefore that any option involving changing the default branch temporarily is not possible for us.

Thank you for your inputs on the matter

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[Tamanna-Sharma8]

Currently, assigning an issue to Copilot through the GraphQL API typically works only when the operation is performed against the repository’s default branch. If you attempt this from a different branch, the assignment may fail because some automation and Copilot-related workflows are tied to the default branch configuration.

To work around this issue, you can:
• Perform the assignment while targeting the default branch.
• Merge or sync your working branch with the default branch before making the API call.
• Ensure repository workflows or automation required for Copilot assignment exist on the default branch.

If this limitation affects your workflow, reporting it through GitHub support or discussions can help bring attention to improving multi-branch support in future updates.

[Kreestyan]

Since then there have been some changes - in case someone ends up here in a search for a solution.
Check out this page: Pick the repository and base branch when assigning issues to Copilot, it explains everything on how to achieve it.

[Kreestyan]

found the solution myself :-(