Claude Code、Codex 與 Gemini CLI 2026 年 10 月 18 日當週更新一覽

Originally published at https://aicoding-guide.com.

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 (idleCompaction turns it off)

Codex 0.163.0 made Daybreak the default for eligible accounts again

CLAUDE_CODE_DISABLE_FILE_MENTIONS and CLAUDE_CODE_AUTO_MODE_MODEL were 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 WorktreeCreate hook 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 is Ctrl+X. Voice mute moved to F9
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 /config or 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 with CLAUDE_CODE_IDLE_COMPACT_MIN_TOKENS, toggle it in /config
CLAUDE_CODE_DISABLE_FILE_MENTIONS passes @ 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