Update Claude Code to 2.0.21 and GitHub Copilot CLI to 0.0.343

[Copilot]

Summary

Updates the default CLI versions for agentic workflow engines to their latest stable releases. This includes 2 CLI version bumps and automatic recompilation of all 26 workflow lock files.

Changes

Version Updates

Claude Code: 2.0.19 → 2.0.21

• Published by wolffiex@anthropic.com
• Two intermediate versions released (2.0.20, 2.0.21)
• Package size remains consistent at 78.5 MB (52 files)
• No breaking changes identified

GitHub Copilot CLI: 0.0.342 → 0.0.343

• Release date: 2025-10-16
• New Features:
  • Added Haiku 4.5 model support (use /model slash command)
  • Added --additional-mcp-config flag for augmenting MCP server configuration
  • Added prompt for multi-line input setup via /terminal-setup
• Bug Fixes:
  • Improved Windows-style path handling (fixes Add link to workflow run when @alias used in a comment #261)
• UI Improvements:
  • Shimmer effect on "Thinking..." indicator
  • Removed box around user messages in timeline
  • Increased contrast for diff highlights
  • Improved slash command cycling
  • Aligned permission/confirmation prompts

View full changelog →

Files Modified

• pkg/constants/constants.go: Updated DefaultClaudeCodeVersion and DefaultCopilotVersion constants
• 26 workflow .lock.yml files: Automatically recompiled with new CLI versions

Validation

✅ All 64 workflow files compiled successfully
✅ Go linting passed with no issues
✅ JavaScript linting passed with no issues
✅ All 534 JavaScript tests passed
✅ Code formatting validated
✅ Binary built successfully
✅ Git status clean - only expected files modified

Impact

Risk Level: Low
Affected Features: All workflows using Claude (engine: claude) and Copilot (engine: copilot) engines
Migration Required: No - backward compatible updates
Notable Benefits: Haiku 4.5 model availability, improved Windows path handling, better MCP configuration flexibility for testing

Testing

The version changes were applied through the standard process:

1. Updated version constants in pkg/constants/constants.go
2. Rebuilt the gh-aw binary with make build
3. Recompiled all workflows with make recompile
4. Validated with make fmt, make lint, and make test-js

All workflows will automatically use the new CLI versions on their next execution.

Original prompt

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This section details on the original issue you should resolve

<issue_title>[ca] Update Claude Code to 2.0.21 and GitHub Copilot CLI to 0.0.343</issue_title>
<issue_description>## Summary

Automated update of agentic CLI tool versions to latest stable releases. This update includes 2 CLI version bumps and recompilation of all workflow lock files.

Updated CLIs

1. Claude Code

• Previous: 2.0.19 → New: 2.0.21
• Release Timeline: Two intermediate versions (2.0.20, 2.0.21)
• Published: Version 2.0.21 published by wolffiex@anthropic.com

Changes:

• Breaking Changes: None identified
• New Features: Unable to retrieve detailed changelogs from NPM registry or GitHub releases
• Bug Fixes: Unable to retrieve detailed changelogs
• Security: No CVEs or security patches identified
• Performance: Package size remains consistent at 78.5 MB (52 files)

Impact Assessment:

• Risk Level: Low
• Affected Features: All workflows using Claude Code engine (claude)
• Migration Required: No - backward compatible update

Notes:

• Detailed changelog not available in NPM registry metadata
• Repository: https://github.com/anthropics/claude-code (no releases published on GitHub)
• Both intermediate versions (2.0.20 and 2.0.21) maintain same package structure and size
• No production dependencies; only optional Sharp image processing libraries for different platforms

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2. GitHub Copilot CLI

• Previous: 0.0.342 → New: 0.0.343
• Release Date: 2025-10-16
• Timeline: 1 day after previous version (0.0.342 released 2025-10-16)

Changes:

• Breaking Changes: None

• New Features:

  • Added Haiku 4.5 model support (use /model slash command to equip)
  • Added --additional-mcp-config flag to augment MCP server configuration per session
    • Supports inline JSON: copilot --additional-mcp-config '{...}'
    • Supports file input: copilot --additional-mcp-config @/path/to/config.json
    • Supports multiple flags with later values overriding earlier ones
  • Added prompt for users to run /terminal-setup for multi-line input support

• Bug Fixes: None explicitly listed

• Improvements:

  • Improved prompts to ensure Windows-style paths on Windows (fixes githubnext/gh-aw#261)
  • Various visual improvements:
    • Added shimmer effect to "Thinking..." indicator
    • Removed box around user messages in timeline
    • Increased contrast of removed intraline highlights in diffs
    • Allow cycling through slash commands from bottom to top
    • Aligned permission/confirmation prompts for consistent visual style

Impact Assessment:

• Risk Level: Low
• Affected Features: All workflows using Copilot CLI engine (copilot)
• Migration Required: No - backward compatible update
• Notable Benefits:
  • New Haiku 4.5 model availability
  • Improved MCP configuration flexibility for testing
  • Better Windows path handling

Changelog Link: https://github.com/github/copilot-cli/releases/tag/v0.0.343

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CLIs With No Updates

3. OpenAI Codex

• Current Version: 0.46.0
• Latest Available: 0.46.0 ✓ Up to date
• Status: No update required

4. GitHub MCP Server

• Current Version: v0.18.0
• Latest Available: v0.18.0 ✓ Up to date
• Released: 2025-10-10
• Status: No update required
• Note: This was a major release with breaking changes to toolset configuration and PR tool consolidation

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Testing & Validation

✅ All 26 workflow lock files successfully recompiled with new versions
✅ No compilation errors or warnings
✅ Git status verified - only expected files modified
✅ No unintended file changes in workflows

Files Changed

• pkg/constants/constants.go - Updated version constants
• 26 workflow .lock.yml files - Recompiled with new CLI versions

Recommendations

1. Deploy: Low risk update, safe to merge
2. Monitor: Watch for any unexpected behavior in workflows using Claude or Copilot engines
3. Benefit: Users get latest features including Haiku 4.5 support and better Windows compatibility
4. Future: Consider subscribing to GitHub release notifications for these repositories to track changes more easily

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Update Process

This update was performed by the automated CLI Version Checker workflow following the standard process:

1. ✅ Fetched latest versions from NPM registry and GitHub releases
2. ✅ Compared with current versions in constants.go
3. ✅ Researched changes and assessed impact
4. ✅ Updated version constants
5. ✅ Ran make recompile to update all workflows
6. ✅ Verified compilation success
7. ✅ Created this PR with detailed analysis

🤖 Generated with Claude Code

AI generated by CLI Version Checker

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[!NOTE]
This was originally intended as a pull request, but the git push operation failed.

Workflow Run: [View run details and downloa...

Fixes #1845

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💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.