# Claude Code 2.1.212: /fork becomes a background session, /subtask added, runaway-loop caps

> `/fork` now copies the conversation into its own background session and the old in-session subagent behavior moves to `/subtask`. New per-session ceilings cap web searches and subagent spawns, MCP calls over 2 minutes auto-background, and the Task tool's `mode` parameter is deprecated and ignored.

| | |
|---|---|
| **Tool** | Claude Code |
| **Version** | 2.1.212 |
| **Kind** | release |
| **Published** | 2026-07-16 |
| **Observed** | 2026-08-11 |
| **Significance** | 4/5 |
| **Breaking** | yes |
| **Categories** | breaking, feature, fix, deprecation, security, api-change |

## What changed


- `/fork` copies the conversation into a new background session with its own `claude agents` row; the previous in-session subagent is now `/subtask`
- Task tool `mode` parameter deprecated and ignored — subagents inherit the parent session's permission mode
- Session caps: WebSearch calls default 200 (`CLAUDE_CODE_MAX_WEB_SEARCHES_PER_SESSION`), subagent spawns default 200 (`CLAUDE_CODE_MAX_SUBAGENTS_PER_SESSION`, reset by `/clear`)
- MCP tool calls over 2 minutes auto-background; tune with `CLAUDE_CODE_MCP_AUTO_BACKGROUND_MS`
- Added `claude auto-mode reset` (confirmation prompt, `--yes` to skip)
- Fixed plan mode auto-running file-modifying Bash commands (`touch`, `rm`) with no permission prompt or SDK `canUseTool` callback
- Fixed worktree creation following a committed symlink at `.claude/worktrees`, which could write outside the repository
- Fixed a `continue:false` hook halt being dropped on mid-stream tool failure, and hook infrastructure errors reported as user rejections
- Fixed SIGTERM orphaning a Bash process tree in print/SDK mode; the CLI now kills the tree and exits 143
- Fixed `/background` and `claude --bg` failing with `uv_spawn` errors on Windows when Group Policy blocks PowerShell 5.1
- Several `/ultrareview` fixes: PR references like `#123` and pasted URLs, fetching remote branches, billing confirmation after `/clear`
- `/resume` in the agent view opens a picker of past sessions, including deleted ones, and resumes as a background session
- Fixed conversations with many images failing with "Request too large"; web search/fetch retry 529 and rate-limited requests with bounded backoff
- `SendMessage` bodies no longer duplicated into replayed history and tool results
- Prompt caching's mid-conversation system block now works behind gateways and custom base URLs
- OpenTelemetry: fixed chunked-encoding rejections (411/400) from Azure Monitor, and missing `trace_id`/`span_id` when `TRACEPARENT` is set

Note: the source entry is truncated mid-bullet at the end (Enterprise `forceLoginMethod` enforcement).


## Sources

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

## Community

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and never blended._

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Canonical: https://changelogs.info/claude-code/2-1-212
Entity: https://changelogs.info/claude-code
Event ID: `evt_2026-07-16_claude-code_2-1-212`
Licence: event synthesis © changelogs.info, CC BY 4.0. Linked sources belong to their vendors.