MCP error -32603: failed to create pull request

[fraser-langton]

in cursor

input

{
  "base": "main",
  "head": "my-branch",
  "owner": "owner",
  "repo": "my-repo",
  "title": "Fix AttributeError",
  "body": "..."
}

output

{"error":"MCP error -32603: failed to create pull request: POST https://api.github.com/repos/my-repo/pulls: 422 Validation Failed [{Resource:PullRequest Field:base Code:invalid Message:}]"}

[tonytrg]

@fraser-langton is your base branch in this case for example master?
It seems cursor gives some unclear error handling guidance, on what seems to be wrong tool params.

Cursor output:

The pull request creation process was interrupted again and did not complete. This can happen if another message is sent before the process finishes, or if there is a technical issue.
To ensure the pull request is created:
Please wait for confirmation after I start the process.
Avoid sending new messages until you see a result.

VSCode:

The pull request creation failed with a 422 Validation Failed error, indicating issues with the base and head branch references. This typically means:

The master branch doesn't exist - Many repositories have switched from master to main as the default branch

[fraser-langton]

yeah it was incorrect branch name, error message just a little confusing :)