# Claude Code 2.1.203: background agent reliability, worktree isolation and memory fixes

> A large fix release centred on background agents: sessions that went permanently unresponsive, subagents silently stopped and restarted from scratch, and worktree-isolated agents running commands in the parent checkout. Also fixes a per-turn CPU and memory regression in interactive sessions and cuts ~7 MB from both binary size and startup memory.

| | |
|---|---|
| **Tool** | Claude Code |
| **Version** | 2.1.203 |
| **Kind** | release |
| **Published** | 2026-07-07 |
| **Observed** | 2026-08-11 |
| **Significance** | 3/5 |
| **Breaking** | no |
| **Categories** | fix, feature, api-change |

## What changed


- Fixed a memory and per-turn CPU regression: the context-usage indicator no longer re-analyzes the whole transcript each turn
- Fixed returning to `claude agents` silently stopping running subagents and re-running the prompt from scratch
- Fixed background sessions becoming permanently unresponsive to attach/reply/stop when the daemon's session token went stale
- Fixed 15–20s stalls opening/switching background sessions on macOS from false low-memory detection (regression in 2.1.196)
- Fixed worktree-isolated subagents running shell commands in the parent checkout; worktree creation rejecting nested repos in multi-repo workspaces
- Fixed background/agent-view sessions dropping a shell-exported `ANTHROPIC_BASE_URL`, which sent API keys to the default endpoint and failed with 401
- Fixed background agents inheriting a stale `PATH` from the daemon (missing tools on Windows), crash-looping on a deleted/invalid working directory, and a daemon auto-upgrade failure silently killing all running sessions
- Fixed `TaskStop`/`TaskOutput` not finding agents spawned by another agent; errors now list running agents by id and description
- Fixed Bash "argument list too long" in repos with many git worktrees
- New: login-expiry warning before background sessions are interrupted; grey ⏸ footer badge in manual permission mode; additional working directories exposed via MCP `roots/list` with `notifications/roots/list_changed`
- Behaviour: left arrow no longer closes background tasks, diff and workflow detail views — use Esc; startup "claude command missing or broken" warnings moved to `/doctor` and `/status`
- Subagents are less likely to re-delegate their entire task to another subagent
- Binary size and startup memory each reduced ~7 MB via lazy loading of a bundled dependency
- [VSCode] Settings toggle for "Enable Remote Control for all sessions"


## Sources

- [changelog_md](https://github.com/anthropics/claude-code/blob/main/CHANGELOG.md) — retrieved 2026-08-11

## Community

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Canonical: https://changelogs.info/claude-code/2-1-203
Entity: https://changelogs.info/claude-code
Event ID: `evt_2026-07-07_claude-code_2-1-203`
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