This week in Claude Code, Codex and Gemini CLI (week of October 18, 2026)
Claude Code now compacts idle conversations on its own, and Codex turned Daybreak back on by default. Plus the environment variables added in 2.1.299 to 2.1.302.
Contents
The change with the widest reach this week is idle compaction in Claude Code. Leave a long conversation sitting and it now gets summarised on its own.
On the Codex side, Daybreak is enabled by default again — a setting that only became an explicit opt-in five days earlier in v0.161.0. It has flipped twice in under a week.
KEY POINT
This week in brief
- Claude Code compacts idle conversations automatically (
idleCompactionturns it off) - Codex 0.163.0 made Daybreak the default for eligible accounts again
CLAUDE_CODE_DISABLE_FILE_MENTIONSandCLAUDE_CODE_AUTO_MODE_MODELwere added
Claude Code
Four releases this week, 2.1.299 through 2.1.302.
Idle compaction arrived (2.1.299, 2.1.302)
The CHANGELOG wording is: "Added idle compaction in the terminal: a 200K+ token conversation left idle for about 54 minutes is compacted before its one-hour prompt cache expires, so your next message doesn't reprocess it all."
The motivation is cost. Leave a conversation above 200K tokens idle for roughly 54 minutes and it is summarised before the one-hour prompt cache expires, so your next message does not pay to reprocess everything. The prompt caching documentation also notes that Claude Code may compact when idle, and that idleCompaction disables it.
| Setting | What it does |
|---|---|
"idleCompaction": false | Turns off automatic idle compaction (v2.1.290+) |
CLAUDE_CODE_IDLE_COMPACT_MIN_TOKENS | Changes the 200K token threshold (v2.1.290+) |
Idle compaction row in /config | Toggles it from the UI (added in v2.1.302) |
Know what compaction drops before you leave it on
Compaction replaces the conversation layer with a summary. CLAUDE.md itself is re-read from disk, but the contents of files that Claude read because CLAUDE.md told it to are folded into the summary. Context management with /compact and /clear covers the difference. If your workflow depends on what is in the window, turn it off.
New environment variables (2.1.299, 2.1.301, 2.1.302)
| Variable | What it does |
|---|---|
CLAUDE_CODE_DISABLE_FILE_MENTIONS | Claude gets the paths of @ file mentions rather than their contents, and reads them with its own file tools |
CLAUDE_CODE_AUTO_MODE_MODEL | Chooses the model the client-side auto mode classifier uses. It does not change server-side auto mode |
CLAUDE_CODE_RETRY_WATCHDOG_MAX_USAGE_LIMIT_WAIT_MS | In unattended retry mode, exits instead of waiting out a usage limit whose reset is too far off |
CLAUDE_CODE_DISABLE_FILE_MENTIONS is the useful one if @-mentioning a large file keeps filling your context in one shot.
Security fixes (2.1.301, 2.1.302)
- The Read tool loaded an image file of any size — or a pipe or device named like an image — entirely into memory. Image sources over 128 MB are now refused
- Quitting removed a worktree made by a
WorktreeCreatehook without asking, even when it might hold unpushed commits
Telemetry
The OpenTelemetry api_request event now splits cache writes by lifetime with cache_creation_5m_tokens and cache_creation_1h_tokens. The tool_decision event gained classifier_verdict, permission_mode and classifier_category, so you can tell an auto mode classifier decision apart from one made by a permission rule.
Codex
Daybreak is the default again (0.163.0)
The release notes say "Daybreak is enabled by default for eligible accounts." In v0.161.0 it required --enable cli_daybreak or features.cli_daybreak=true, and daybreak=true alone was not enough (What changed in Codex CLI v0.161 and v0.162). Five days and a reversal later, this is not a setting to treat as settled.
/config and steering (0.163.0)
/config: search preferences across categories, change supported ones in place, and see which changes need a restart- Follow-ups mid-response: send a follow-up while Codex is responding to steer it immediately. Interrupting a turn also stops running Code Mode cells and nested tool calls
- Leader key in
/keymap: the default isCtrl+X. Voice mute moved toF9 - Parallel read-only tools: independent reads such as skills, memories and conversation history now run in parallel
Network and sandbox (0.163.0)
Three proxy fixes landed: the network proxy now checks permission before a DNS lookup, rejects duplicate Host headers, and prevents credential aliases from bypassing inspection hooks. Resuming a saved thread now restores its permission and network approvals too.
One operational change: Codex no longer bundles a patched zsh and uses its standard shell executor instead. Configurations using the retired shell flags get a migration notice.
Gemini CLI
v0.64.0 is fixes only. The notable ones: a CPU hang and swallowed quotes when @ appears in code, file tool operations serialised with atomic writes, and atomic state persistence with recovery from a backup when the file is corrupt. On Windows, ConPTY now forwards the IME cursor position.
What to check now
- Decide how you feel about idle compaction. If you do not want conversations summarised unprompted, turn it off in
/configor with"idleCompaction": false - If you had explicitly disabled Daybreak in Codex, check its current state — the default moved
- Upgrade Claude Code to 2.1.302 or later if the Read tool image issue matters to you
- Upgrade Codex to 0.163.0 if you restrict network access in the sandbox, for the pre-DNS permission check
Summary
- Claude Code now compacts idle conversations: 200K+ tokens left for about 54 minutes
- Turn it off with
"idleCompaction": false, tune it withCLAUDE_CODE_IDLE_COMPACT_MIN_TOKENS, toggle it in/config CLAUDE_CODE_DISABLE_FILE_MENTIONSpasses@mentions as paths instead of contents- Codex 0.163.0 made Daybreak the default again for eligible accounts, reversing v0.161.0
- Gemini CLI v0.64.0 is fixes only
FAQ
- How do I turn off idle compaction?
- Set idleCompaction to false in settings.json, or use the Idle compaction row in /config on v2.1.302 and later. CLAUDE_CODE_IDLE_COMPACT_MIN_TOKENS changes the threshold.
- Did the Codex Daybreak setting change again?
- Yes. v0.161.0 required an explicit cli_daybreak opt-in, but the v0.163.0 notes say Daybreak is enabled by default for eligible accounts.
- Which change should I act on first?
- Idle compaction. A long conversation you leave open now gets summarised without you asking, so turn it off if that is not what you want.
Primary sources
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