The tool already commits directly to any existing branch (BranchExists→upsert, no create — covered by TestFileWriteBranchSkipsCreateWhenBranchExists), so `branch:"main"` is a one-call direct-to-main write. The descriptor said "feature branch", understating it. pr_create/pr_merge/repo_list already exist, closing the other two #35 gaps (PR loop + owner repo listing). Descriptor now states both paths. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>