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Claude Code Week 14 Release Digest (March 30 – April 3, 2026)

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Source: Anthropic What’s New — Week 14 Type: Release Notes Releases: v2.1.86 → v2.1.91 Date Range: March 30 – April 3, 2026

Five headline features, nine smaller wins. Computer use crosses from Desktop to CLI (research preview). /powerup ships in-terminal lessons. Flicker-free rendering debuts the alt-screen renderer that paves the way for Week 15’s Ctrl+O focus view. MCP authors gain per-tool result-size overrides up to 500K, and plugins can ship executables on PATH via a bin/ directory.

Headline features

Computer use in the CLI (research preview)

Last week computer use landed in Claude Code Desktop (Week 13). This week the CLI gets it: open native apps, click through UI, take screenshots, fix what breaks — all from the terminal. Web apps already had verification loops; native iOS, macOS, GUI-only apps now do too. Best for closing the loop on apps where there’s no API to call. Run /mcp, find computer-use, toggle on. Full coverage in Computer Use.

/powerup (v2.1.90)

Interactive in-terminal lessons that teach Claude Code features via animated demos. Run once, learn what shipped while you weren’t looking. With weekly releases the surface drifts fast — /powerup is the catch-up loop.

Flicker-free rendering (v2.1.89)

New alt-screen renderer with virtualized scrollback. Prompt input pinned to the bottom, mouse selection works across long conversations, no redraw flicker. Opt in:

export CLAUDE_CODE_NO_FLICKER=1
claude

This is the substrate for Week 15’s Ctrl+O focus view. See Week 15 and CLI reference.

MCP result-size override (v2.1.91)

MCP server authors can raise the truncation cap on a specific tool by setting anthropic/maxResultSizeChars in the tool’s tools/list _meta, up to a 500K hard ceiling. Used to be global; now schemas / file trees / large payloads can stay inline when the tool needs them. See Essential MCP Servers for context.

{
  "name": "get_schema",
  "description": "Returns the full database schema",
  "_meta": { "anthropic/maxResultSizeChars": 500000 }
}

Plugin executables on PATH (v2.1.91)

Drop a bin/ directory at the plugin root. Claude Code adds it to the Bash tool’s PATH while the plugin is enabled. Bare commands; no absolute paths or wrapper scripts. See Plugins and Marketplaces.

my-plugin/
├── .claude-plugin/
│   └── plugin.json
└── bin/
    └── my-tool

Other wins

  • PermissionDenied hook — fires when the auto-mode classifier denies a tool call. Return retry: true to let Claude try a different approach. /permissions → Recent retries manually with r.
  • defer in PreToolUse for -p sessions — pause at a tool call and exit with a deferred_tool_use payload so an SDK app or custom UI can surface the decision; resume with --resume. See Hooks for the full permissionDecision matrix.
  • /buddy — April 1st gag. Hatches a small creature that watches you code.
  • disableSkillShellExecution setting — blocks inline shell from skills, slash commands, and plugin commands.
  • Edit-after-cat/sed — Edit tool now works on files that were viewed via cat or sed -n, no separate Read required.
  • Hook output >50K → disk — large hook stdout/stderr is saved to disk with a path + preview instead of injected into context.
  • Thinking summaries off by default in interactive sessions. Restore with showThinkingSummaries: true. See Extended Thinking.
  • Voice mode improvements — push-to-talk modifier combos, Windows WebSocket, macOS Apple Silicon mic permission.
  • claude-cli:// deep links accept multi-line prompts (encoded %0A).

Key Takeaways

  • Computer use is now end-to-end on macOS CLI + Desktop; iOS simulator drive-throughs are a first-class workflow.
  • The bin/ PATH plugin pattern means plugins ship full CLI helpers, not just commands/agents/hooks. Closes a long-standing distribution gap.
  • maxResultSizeChars solves the “large schema” problem for MCP servers — previously these hit the global cap and got persisted to disk with a file reference.
  • Hook surface continues to grow: PermissionDenied event, defer exit-with-payload in non-interactive mode, disableSkillShellExecution lockdown switch.
  • Flicker-free renderer is the foundation: this week opt-in via env var, next week ships Ctrl+O focus view on top.

Try It

  1. Toggle computer-use on via /mcp and have Claude open Simulator.app, run an iOS test, screenshot each step.
  2. Set CLAUDE_CODE_NO_FLICKER=1 and reopen — long sessions become genuinely usable for selection / scroll.
  3. If you maintain an MCP server with a “give me the full schema” tool, add anthropic/maxResultSizeChars: 500000 and stop persisting that result to disk.
  4. Bundle a CLI helper in a private team plugin: drop the binary in bin/, install the plugin, call it as a bare command from any Bash tool call.
  5. In a -p script, set permissionDecision: "defer" on a sensitive tool call; surface the deferred_tool_use payload in your UI; resume with --resume.

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