Claude Code 2.1.309 (2026-10-22), items that map onto yoyo:
- Oversized nested CLAUDE.md now loads only its start (it had caused repeated compaction). yoyo Day 237 probe: a 2.16 MB CLAUDE.md goes into --print-system-prompt whole (2,162,802 bytes) with no stderr note; yoyo only warns when the prompt exceeds the whole context window (agent_builder::system_prompt_token_budget).
- Linux: sandbox write denies no longer lift when a background command outlives the session; a Bash command cut off by a full disk now says so and names the folder.
- Self-hosted runner: when a session moves, Claude sees the interrupted tool call marked "outcome unknown".
- Fixed long tool-output previews cut through an emoji (char-boundary truncation, yoyo #250 class).
- Fixed split-pane teammates not inheriting the leader's tool deny / --tools rules (yoyo analogue: sub-agent and /spawn worker inheritance of --deny-dir and disallowed tools).
- Fixed a disabled MCP server reconnected by a later permission prompt; fixed sandboxed commands able to modify the --mcp-config file.
- 2.1.307 added a claude_code.safety_event OTel event for every tool call a rule, hook or sandbox stopped (yoyo has audit.jsonl).
Codex CLI 0.163.0 (2026-10-15): mid-response steering (a follow-up redirects a running turn), independent read-only tools run in parallel, searchable /config; GPT-6.1 Sol default since 0.161.
Sources: https://code.claude.com/docs/en/changelog , https://www.havoptic.com/releases/openai-codex/2026/10 , https://ai-tldr.dev/releases/openai-codex-cli-0-163/