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Claude Code Week 17 Release Digest (April 20–24, 2026)

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Source: Anthropic What’s New — Week 17 Type: Release Notes Releases: v2.1.114 → v2.1.119 Date Range: April 20–24, 2026

Four headline features. /ultrareview opens to public research preview after debuting in Week 16. Session recap becomes a headline feature — automatic on terminal return, /recap on demand. Custom themes let you build and ship named color themes from /theme or ~/.claude/themes/, with plugin distribution support. Claude Code on the web gets a visual redesign matching the desktop app. Twelve smaller wins including hooks calling MCP tools directly, /cost + /stats merged into /usage, /config now persists to ~/.claude/settings.json, forked subagents, --from-pr GitLab/Bitbucket/GHE support, and Opus 4.7’s 1M context window fixed.

Headline features

/ultrareview (public research preview)

Now open to all — runs a fleet of bug-hunting agents in the cloud against your branch or a PR, findings land back in CLI or Desktop automatically. Recommended before merging critical changes (auth, data migrations, security-sensitive paths).

> /ultrareview
> /ultrareview 1234

See Ultrareview for full coverage including pricing (3 free runs for Pro/Max, then 20 as extra usage), auth constraints (Claude.ai account required; not available on Bedrock/Vertex/Foundry/ZDR), and the comparison table with local /review.

Session recap

Switch focus away from a session, come back to a one-line recap of what happened. Automatic on return; run /recap on demand; disable from /config. Helps stay in flow across multiple concurrent sessions.

> /recap

Custom themes (v2.1.118)

Build and switch between named color themes from /theme or by editing JSON files in ~/.claude/themes/. Each theme picks a base preset and overrides only the tokens it needs. Plugins can ship themes too.

> /theme

See Plugins and Marketplaces for the plugin theme distribution pattern.

Claude Code on the web redesign

Claude.ai/code now matches the redesigned desktop app: sessions sidebar, drag-and-drop layout, refreshed routines view. Core parts rebuilt for quicker responses and reliability. Routines gets a dedicated updated view in this redesign.

Other wins

  • Vim visual mode — press v for character selection or V for line selection in the prompt input, with operators and visual feedback. See CLI Reference.
  • Hooks can call MCP tools directly — new type: "mcp_tool" hook field lets a hook hit an already-connected MCP server without spawning a subprocess. See Hooks.
  • /cost + /stats merged into /usage — old names still work as shortcuts that open the relevant tab. See CLI Reference.
  • /config persists to ~/.claude/settings.json — theme, editor mode, verbose, and similar settings now follow the project/local/policy precedence chain and survive restarts.
  • Forked subagents — CLAUDE_CODE_FORK_SUBAGENT=1 on external builds enables a fork that inherits the full conversation context instead of starting fresh. See Claude Code Subagents.
  • Default effort raised to high for Pro/Max on Opus 4.6 and Sonnet 4.6 (was medium). Combined with Week 15’s change (non-subscription tiers to high), all tiers except those locked at lower effort are now at high or xhigh. See Opus 4.7 Best Practices.
  • Native builds replace Glob+Grep — embedded bfs and ugrep available through Bash, for faster file searches without a separate tool round-trip.
  • --from-pr now accepts GitLab MRs, Bitbucket PRs, GitHub Enterprise in addition to github.com.
  • Auto mode $defaults — include "$defaults" in autoMode.allow, soft_deny, or environment to add custom rules alongside the built-in list instead of replacing it entirely.
  • claude plugin tag — creates release git tags for plugins with version validation. See Plugins and Marketplaces.
  • Opus 4.7 native 1M context — sessions now compute against the model’s actual 1M context window, fixing inflated /context percentages and premature autocompaction that was a known issue post-W16 launch.
  • /resume 67% faster on large sessions; now offers to summarize stale, large sessions before re-reading them.

Key Takeaways

  • /ultrareview going public is the primary deployment signal: it’s real, priced, and ready to embed in team workflows. The W16 debut was narrower; this is the general availability push.
  • Session recap fills a real gap in multi-session workflows. If you leave a session running for 20 minutes and come back, you no longer have to scroll to understand what happened.
  • Custom themes have a plugin distribution path — this is more than cosmetics. Teams with brand standards or accessibility requirements can now ship a single plugin that enforces a color scheme organization-wide.
  • Hooks calling MCP tools directly (type: "mcp_tool") is a structural improvement: hooks previously had to spawn subprocesses to reach MCP servers. Now a PostToolUse hook can call an MCP tool inline without subprocess overhead. First-class parity between hook callbacks and normal tool use.
  • /config persisting is a usability fix that’s been implied by the settings system but never worked right. Settings you set in one session now follow you across sessions without re-applying.
  • --from-pr GitLab/Bitbucket/GHE is significant for enterprise deployments that aren’t on github.com. Multi-platform code review workflows are now first-class.
  • Opus 4.7 1M context fix is quietly load-bearing. The W16 launch of Opus 4.7 had an issue where /context showed inflated percentages and sessions compacted too early. This resolves it — sessions running the new model will stop compacting prematurely.

Try It

  1. Try /ultrareview now it’s public. Pick a PR with auth or migration changes. Run /ultrareview <PR>. Compare the verified findings against what a quick local /review would have caught.
  2. Run multiple sessions and test recap. Kick off a long-running task in one terminal, switch focus, come back. Hit /recap to see the summary. Adjust the detail level from /config if needed.
  3. Build a custom theme. Run /theme, pick “create new,” override 2–3 color tokens from a base preset, save it. If you’re a plugin author, consider shipping the theme as part of your plugin.
  4. Add a type: "mcp_tool" hook. If you have a PostToolUse hook that currently shells out to an MCP server via subprocess, refactor it to use type: "mcp_tool" and measure the response time improvement.
  5. Check /context on Opus 4.7. If you’ve seen inflated percentages or early autocompaction since W16, upgrade to v2.1.117+ and confirm the 1M window is reporting correctly.
  6. Test --from-pr with GitLab or Bitbucket. Paste a GitLab MR URL or Bitbucket PR URL to confirm the new multi-platform support.

Update — Rate limits doubled (May 7 conference)

[Reddit signal — r/ClaudeCode 2026-05-06] Two weeks after this digest, Anthropic announced at Code with Claude 2026 that Claude Code 5-hour session limits would double across Pro/Max/Team, peak-hours throttling for Pro/Max would be removed, and Opus API rate limits would jump significantly. Funded by a SpaceX Colossus 1 compute partnership (220k+ Nvidia GPUs, 300+ MW capacity). Source: raw/reddit-1t5hs98.md (1183 upvotes, the @claudeai post in the thread root). Full coverage: Anthropic + SpaceX Rate-Limit Increase. Same conference week shipped six Claude Code releases — see Week 19 Release Digest.

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