DevAgentRadar → Claude Code

You are helping me adopt a real coding-assistant change. Work only from the facts below. Do not invent features.

Context

Assistant: Claude Code Proposal: Set CLAUDE_CODE_IDLE_COMPACT_MIN_TOKENS and disable @-mention file stuffing Summary: Claude Code v2.1.299 compacts idle 200K+ token terminal chats ~54 minutes before the 1-hour prompt cache expires, and can give Claude @-mention paths instead of file contents. Set CLAUDE_CODE_IDLE_COMPACT_MIN_TOKENS and CLAUDE_CODE_DISABLE_FILE_MENTIONS; do not set idleCompaction false. Primary source: https://github.com/anthropics/claude-code/releases/tag/v2.1.299

Why it matters

Long terminal sessions that sit idle used to miss the 1-hour prompt cache and then reprocess the full conversation. v2.1.299 (idle compaction needs v2.1.290 or later) now compactes a 200K+ token conversation left idle about 54 minutes before that cache expires, so the next message does not reprocess it all. Change the 200K floor with CLAUDE_CODE_IDLE_COMPACT_MIN_TOKENS. Only put "idleCompaction": false in settings.json if you want that off. CLAUDE_CODE_DISABLE_FILE_MENTIONS makes @-mentions pass paths so Claude reads files with its file tools instead of injecting contents into the prompt. In agent view, /effort and /fast set what new sessions start with; a bare /model, /effort or /fast opens a picker. Upgrade also closes a sandbox hole: a sandboxed shell command could write into --plugin-dir, whose code Claude Code reloads and runs outside the sandbox.

Suggested actions

1. Upgrade Claude Code to v2.1.299 (idle compaction requires v2.1.290 or later) and confirm with: claude --version
2. export CLAUDE_CODE_DISABLE_FILE_MENTIONS=1
3. export CLAUDE_CODE_IDLE_COMPACT_MIN_TOKENS=100000
4. In settings.json leave idle compaction on (do not add "idleCompaction": false) so a 200K+ token terminal conversation idle ~54 minutes is compacted before the 1-hour prompt cache expires.
5. In agent view, run /effort or /fast to set what new sessions start with; a bare /model, /effort or /fast now opens a picker.

Config surfaces this release may change

• context and compaction settings (high confidence) — check your repo before applying
• hooks (high confidence) — check your repo before applying
• sandbox settings (high confidence) — check your repo before applying
• settings files (high confidence) — check your repo before applying
• background and headless runs — check your repo before applying
• MCP servers — check your repo before applying
• permission rules — check your repo before applying
• skills — check your repo before applying
• subagent definitions — check your repo before applying

After you finish

Do not report this as applied to DevAgentRadar. You cannot write the visitor's loop.

Tell the human: open https://devagentradar.com/proposals/claude-code-v2-1-299-set-claude-code-idle-compact-min-tokens-and-disable and mark Applied, Skipped, or Failed. Proposal id: 946cef01-950c-46aa-b560-f0382f1b3096

Your job

1. Restate the change in one sentence.
2. Propose a minimal plan for my repo (or a throwaway pilot).
3. Implement only what I approve; prefer small diffs and tests.
4. Call out risks (permissions, breaking APIs, cost).

Start by confirming you understood the proposal.