TL;DR

• /code-review now runs as a background subagent. Your conversation stays clear while the review runs, and stacked slash commands keep working as the review target.

• /deep-research no longer launches on its own. If you relied on Claude deciding to deep-research mid-task, you now need to invoke /deep-research manually (more below).

• Subagents no longer spawn nested subagents by default. Set CLAUDE_CODE_MAX_SUBAGENT_SPAWN_DEPTH if your workflows depend on agents delegating to child agents (more below).

• Skills with context: fork now run in the background by default. Add background: false to the skill frontmatter to opt out.

• Concurrent subagent cap is now 20. Override with CLAUDE_CODE_MAX_CONCURRENT_SUBAGENTS if your workflows fan out wider than that.

New in 2.1.218, 2.1.217

2.1.218 (July 23, 2026)

• Changed /code-review to run as a background subagent, so review work no longer fills your conversation and keeps stacked slash commands as its review target
• Added screen-reader announcements of deleted text for word and line deletions (Option+Delete, Ctrl+W, Cmd+Backspace, Ctrl+U, Ctrl+K) in --ax-screen-reader mode
• Fixed Windows paths with \u-prefixed segments (like C:\Users\unicorn) being corrupted into CJK characters in tool inputs, which made those files inaccessible
• Fixed the left arrow key discarding the conversation with no undo: presses right after editing now ask to confirm, and Esc in the agent view returns to the conversation it backgrounded
• Added HTTP status and error text to claude mcp list and /mcp when a server fails to connect, and a warning for MCP config values with hidden leading or trailing whitespace
• Fixed multi-line paste collapsing into one line with j in place of newlines in terminals that encode pasted newlines as Ctrl+J
• Fixed /context reporting stale pre-compact token usage after compacting from the message picker
• Fixed /ultrareview failing on descriptive arguments like "review my auth changes", they now run a review of your current branch with the text applied as a note to the findings
• Fixed /code-review ultra silently running a local review in non-interactive sessions, it now launches the cloud review
• Fixed gateway spend metering to price Bedrock application-inference-profile ARNs and other config-mapped upstream model IDs at the configured model's rates
• Fixed mojibake when a long IDE selection was truncated mid-emoji, and a case where a tool executor error could be silently dropped
• Fixed an engine teardown race that could start and abandon a phantom turn, and made input pushed after close consistently rejected
• Fixed spurious "[Request interrupted by user]" messages after interrupted tool calls, and an unpaired tool_use block left in the transcript when a tool aborted mid-response
• Fixed VoiceOver reading "new line" instead of echoing the typed space at the end of the input in --ax-screen-reader mode
• Fixed plugin and settings panels not moving the terminal cursor to the focused row, so screen readers and magnifiers can follow arrow-key navigation
• Fixed crashes (maximum call stack exceeded) when a deeply nested watched directory tree was deleted or moved, and when rendering deeply nested UI trees
• Fixed pull request events occasionally being lost when a session exited immediately after creating or linking a PR
• Fixed the Bedrock setup wizard failing profile verification for assume-role profiles in partitioned AWS regions and on proxy-only networks
• Fixed rare negative or incorrect turn duration measurements after a system clock adjustment by timing turns with a monotonic clock
• Fixed the "N MCP servers need authentication" startup notice over-counting claude.ai connectors that aren't connected in claude.ai
• Fixed prompt history entries being dropped or duplicated when history writes raced or failed
• Fixed a retry loop that re-sent identical doomed requests after a context-overflow error with a large thinking budget; Ctrl+B backgrounding now applies the same background-shell caps as other paths
• Fixed agent frontmatter hooks running from untrusted folders: hooks now require the agent file's own folder to have accepted workspace trust
• Fixed fork-session lineage being lost after compaction in headless and SDK sessions
• Fixed a resumed session failing every turn, or crashing on resume, when its history held a malformed delta attachment
• Improved /ultrareview error feedback so Claude can correct an invalid argument instead of retrying it unchanged
• Improved auto mode: the dangerous-rm, background-&, and suspicious-Windows-path checks no longer open permission dialogs; the auto-mode classifier adjudicates them instead
• Improved sandbox command restrictions for IDE interactions
• Improved trust dialogs to name the repository root the grant covers
• Changed /deep-research to start only when invoked manually; Claude no longer launches it on its own
• Changed plan mode with auto to no longer prompt for Bash commands the static analyzer can't prove read-only; the auto-mode classifier judges them instead
• Added an announcement when fast mode changes as a result of switching models via /config model=<x> or Remote Control
• Changed server-managed settings so benign feature and cost toggles no longer trigger the settings-approval prompt
• Changed agent markdown files to reject agent names containing :, which is reserved for plugin namespacing
• Changed skills with context: fork to run in the background by default; opt out per skill with background: false
• Added yes/no/on/off/1/0 (case-insensitive) as accepted values for skill and plugin frontmatter booleans, alongside true/false
• Fixed remote sessions continuing to send heartbeats after their worker was replaced, which left long-lived desktop and IDE processes retrying a rejected request every few seconds forever

2.1.217 (July 23, 2026)

• Added emoji shortcode autocomplete in the prompt input: type :heart: to insert a heart, or :hea for suggestions, disable with the emojiCompletionEnabled setting
• Added warnings when transcript writes are failing (e.g. disk full) or when session saving is off due to an inherited environment variable, instead of losing transcripts silently
• Fixed a memory leak where truncated MCP tool outputs kept the full untruncated result in memory for the rest of the session
• Fixed Windows auto-update failures that could leave claude.exe missing; failed updates now restore the preserved executable automatically
• Fixed background session isolation not canonicalizing symlinked working directories, which could let sessions escape their workspace folder
• Fixed auto-compact never triggering for Claude Opus 4.8 on Bedrock and /compact failing once over the limit
• Fixed corporate mTLS, TLS-verify, OAuth scope, and proxy settings being ignored in Claude Desktop sessions
• Fixed screen reader mode's startup announcement being cut off by the first prompt render, and the thinking status row re-rendering every few seconds to update elapsed time and token counts
• Fixed managed settings that set OTEL_EXPORTER_OTLP_ENDPOINT not governing all signals, lower-scope signal-specific overrides no longer redirect telemetry away from the managed endpoint
• Fixed --resume/--continue and /resume failing with a TypeError when a transcript has a malformed attachment entry
• Fixed Remote Control sessions not showing a pending permission prompt or dialog to viewers that connected after it appeared
• Fixed background shells sometimes becoming impossible to stop after a session is sent to the background (/background or left arrow) or when the session exits on a heavily loaded machine, most visible on Windows
• Fixed a CLAUDE.md or SKILL.md paths frontmatter value with many brace groups OOM-killing or stalling the CLI at startup, brace expansion is now budget-bounded
• Fixed the transcript preview sitting flush against the input area when attaching to a starting background session; it now leaves the same one-line gap as the live layout, so the transcript no longer shifts when the session takes over
• Improved footer PR badge links to be clickable hyperlinks even when terminal support can't be detected (e.g. over ssh/tmux); set FORCE_HYPERLINK=0 to opt out
• Changed the login-expiry warning to appear 3 days before expiry instead of 5
• Capped the frontend-design plugin suggestion tip at 3 lifetime impressions instead of repeating indefinitely
• Added a cap on concurrently-running subagents (default 20, override with CLAUDE_CODE_MAX_CONCURRENT_SUBAGENTS) so one message can't fan out unbounded background agents
• Changed subagents to no longer spawn nested subagents by default; set CLAUDE_CODE_MAX_SUBAGENT_SPAWN_DEPTH to allow deeper nesting
• Fixed --max-budget-usd not stopping background subagents: once the cap is reached, new spawns are denied and running background agents are halted

Notes