Describe the bug

The assign_copilot_to_issue tool fails with a GraphQL schema validation error when attempting to assign Copilot to an issue. The error indicates that the agentAssignment field is not defined on the UpdateIssueInput type.

Affected version

Using the MCP server integrated with VS Code Copilot (remote MCP).

Steps to reproduce the behavior

1. Enable the GitHub MCP server in VS Code
2. Create an issue in a repository that has Copilot coding agent enabled
3. Attempt to assign Copilot to the issue using the assign_copilot_to_issue tool with valid owner, repo, and issue_number parameters

Expected vs actual behavior

Expected: Copilot should be assigned to the issue.

Actual: The tool returns an error:

failed to update issue with agent assignment: Variable $input of type UpdateIssueInput! was provided invalid value for agentAssignment (Field is not defined on UpdateIssueInput)

Logs

ERROR while calling tool: MPC 0: failed to update issue with agent assignment: Variable $input of type UpdateIssueInput! was provided invalid value for agentAssignment (Field is not defined on UpdateIssueInput)

_{Created with GitHub Copilot. This issue was written with AI assistance.}