---
title: 'In the News: October 15, 2026 (Morning)'
description: 'Claude Code 2.1.299 compacts a 200K-token session left idle for about 54 minutes, before the prompt cache expires; the default is on and has an opt-out.'
canonical_url: 'https://darkfactory.dev/news/2026-10-15-morning'
markdown_url: 'https://darkfactory.dev/news/2026-10-15-morning.md'
collection: news
date_published: '2026-10-15T07:30:00-04:00'
date_modified: '2026-10-15T07:30:00-04:00'
---

# In the News: October 15, 2026 (Morning)


One item this morning: Claude Code now rewrites a long session on its own while you are away from it. If you leave big sessions open overnight or over lunch, the next turn may start from a compacted conversation instead of the full one.

## 1. Claude Code 2.1.299 compacts long idle sessions before the prompt cache expires

**[Claude Code changelog, version 2.1.299](https://code.claude.com/docs/en/changelog)** · Anthropic · October 14, 2026

The 2.1.299 entry adds idle compaction in the terminal. A conversation of 200K tokens or more that has sat idle for about 54 minutes is compacted before its one-hour prompt cache expires. The changelog gives the reason: "so your next message doesn't reprocess it all." Two controls come with it. `CLAUDE_CODE_IDLE_COMPACT_MIN_TOKENS` changes the 200K-token minimum, and `"idleCompaction": false` in `settings.json` turns the behavior off. The changelog says both need v2.1.290 or later.

The same release adds `/usage` warnings for max effort, workflows, always-on context and large tool results, and a `--disallow-tools` option for `claude plugin eval` that keeps built-in tools such as Agent out of eval runs. We read the 2.1.299 and 2.1.300 sections of the page. The changelog does not say how much the compaction saves, how the summary is built, or whether it applies outside the terminal.

**Why it matters:** The cache window is the cost lever here. A long session that outlives the one-hour cache is expensive to resume, and Anthropic has chosen to trade that cost for a rewritten history. If a session carries state you need verbatim, such as a long spec or a half-finished plan, decide whether to set `idleCompaction` to false or write that state to a file first. Whether the compacted session behaves as well as the original is untested in the changelog.