Failed API calls should not be failures, not errors

[SamMorrowDrums]

An example:

github-mcp-server/pkg/github/context_tools.go

Line 34 in 4ccedee

return nil, fmt.Errorf("failed to get user: %w", err)

As discussed here and here in general failures of this kind are not to be returned as errors, but instead returned as failed tool calls.