Mined Claude Code releases v2.1.207-216 (July 10-20, 2026) fix log for transferable bug classes, per the Day-141 rival-fix-log method. Sources: code.claude.com/docs/en/whats-new, /docs/en/changelog, github.com/anthropics/claude-code/releases/tag/v2.1.216.

Directly transferable to yoyo (verified open on Day 144):

1. WORKTREE GIT ESCAPE — CC fixed "worktree-isolated subagents redirecting git into the shared checkout via git -C, --git-dir, or GIT_DIR/GIT_WORK_TREE". yoyo commands_spawn.rs pins bash cwd to the worktree but has NO handling of git -C / --git-dir / GIT_DIR env (grep confirmed) — this is the exact documented "NOT a sandbox" gap in CLAUDE.md. CC also fixed symlinked-workdir canonicalization for background sessions (yoyo did its symlink pre-flight Day 143 — parallel evolution).
2. UNRESOLVED-VARIABLE rm -rf — CC auto mode now "asks before running rm -rf on a variable it cannot resolve from context". yoyo safety.rs has no distinct check for rm -rf $VAR / "$VAR/" where empty expansion widens the blast radius.
3. TRUNCATED-OUTPUT MEMORY LEAK — CC fixed truncated MCP tool outputs keeping the full untruncated result in memory for the session. yoyo TruncatingTool worth auditing for the same retention.
4. QUADRATIC MESSAGE NORMALIZATION — CC fixed long-session slowdown where per-turn normalization grew quadratically. Relevant to yoagent/yoyo long REPL sessions.

Feature landscape notes: /doctor became fix-capable (finds unused skills/MCP/plugins vs context cost, dedups CLAUDE.md, flags slow hooks, asks before changing) — yoyo /doctor has the cost audit but is read-only-report + separate /fix. Screen reader mode shipped in CC same week yoyo shipped --screen-reader (and CC already has follow-up fixes: startup announcement cut off, thinking-row re-render — likely future yoyo bugs too). /fork copies conversation to a background session. Sonnet 5 is now the default model for Pro seats. In-app browser on Desktop (sandboxed, classifier-reviewed).