Local and file-backed origins do not provide a mergeable GitHub PR surface, so codex-agent now skips the auto-finish merge path in that context and keeps the sandbox available for manual follow-up. The focused regression docs were tightened to match the actual fallback behavior and owner slug handling.

Constraint: Local and file-backed origin remotes cannot satisfy the gh PR merge flow
Rejected: Treat any origin remote as mergeable | it leaves codex-agent waiting on a PR surface that does not exist
Confidence: high
Scope-risk: narrow
Directive: Keep auto-finish gated on a real mergeable remote context unless a test harness explicitly injects a fake gh binary
Tested: openspec validate agent-codex-fix-remaining-cli-ci-failures-2026-04-21-11-42 --type change --strict; openspec validate --specs; node --test --test-name-pattern "codex-agent restores local branch and falls back to safe worktree start when starter script switches in-place" test/install.test.js; node --test --test-name-pattern "codex-agent launches codex inside a fresh sandbox worktree and keeps branch/worktree by default" test/install.test.js
Not-tested: Full node --test test/install.test.js still fails 2 unrelated codex-agent regressions in this stale worktree baseline