Add comprehensive CLAUDE.md for AI assistants

This file provides AI assistants with essential context about:
- Repository purpose (documentation/issue tracking, not source code)
- GitHub Copilot CLI architecture and key features
- Development workflows and conventions
- How to work with issues and documentation
- Quick reference for common scenarios

The guide emphasizes that this is a public docs repository, with
detailed information extracted from the comprehensive changelog and
README to help AI assistants provide accurate, helpful guidance.

Author: claude

CLAUDE.md

@@ -0,0 +1,350 @@
+# CLAUDE.md - AI Assistant Guide for GitHub Copilot CLI Repository
+
+## 🎯 Repository Overview
+
+**IMPORTANT:** This is the **public documentation and issue tracking repository** for GitHub Copilot CLI. The actual source code is maintained separately and distributed as the npm package `@github/copilot`.
+
+This repository serves as:
+- Public documentation and README
+- Issue tracking and community feedback
+- Feature request management
+- Release changelog documentation
+
+**What this repository IS NOT:**
+- Source code repository (no src/ or lib/ directories)
+- Build/test infrastructure
+- Package distribution point
+
+## 📁 Repository Structure
+
+```
+/home/user/copilot-cli/
+├── README.md              # User-facing documentation (installation, usage)
+├── changelog.md           # Comprehensive version history (primary source of architectural info)
+├── LICENSE.md             # Pre-release license terms
+└── .github/
+    ├── ISSUE_TEMPLATE/
+    │   ├── bug_report.yml        # Structured bug report template
+    │   └── feature_request.yml   # Feature request template
+    └── workflows/
+        ├── triage-issues.yml              # Auto-labels new issues
+        ├── close-single-word-issues.yml   # Auto-closes invalid issues
+        ├── stale-issues.yml               # 365-day stale issue management
+        ├── feature-request-comment.yml    # Acknowledges feature requests
+        └── [other issue management workflows]
+```
+
+## 🏗️ GitHub Copilot CLI Architecture
+
+While the source code isn't in this repository, understanding the architecture is crucial for assisting users:
+
+### Core Concepts
+
+**Agentic Architecture:**
+- Built on GitHub's "agentic harness" - an AI agent system
+- Plans and executes complex multi-step tasks
+- Tool-based design pattern (agent calls tools, user approves)
+- Preview-first approach: nothing executes without user confirmation
+
+**Technology Stack:**
+- Node.js v22+ (minimum requirement)
+- npm v10+
+- Cross-platform: Linux, macOS, Windows
+- Shell support: Bash, PowerShell v6+
+
+### Tool System
+
+The CLI uses a tool-calling architecture where the AI can invoke:
+
+**Built-in Tools:**
+- File operations: read, write, edit, glob, grep
+- Shell command execution (with permission system)
+- Git operations
+- Web fetch and search
+
+**GitHub MCP Server Tools** (default, limited set since v0.0.350):
+```
+Code: get_file_contents, search_code, search_repositories
+Git: list_branches, list_commits, get_commit
+Issues: get_issue, list_issues, get_issue_comments, search_issues
+PRs: pull_request_read, list_pull_requests, search_pull_requests
+Workflows: list_workflows, list_workflow_runs, get_workflow_run,
+           get_job_logs, get_workflow_run_logs
+Users: user_search
+```
+
+**Custom MCP Servers:**
+- Extensible via `~/.copilot/mcp-config.json`
+- Support for third-party MCP servers
+
+### Permission System
+
+Sophisticated path-based permission model:
+- Per-path read/write permissions
+- Whitelist/blacklist for tools via `--allow-tool`, `--deny-tool`
+- Glob pattern matching for tool rules
+- Smart heuristics to minimize permission prompts
+
+### Configuration Files
+
+**~/.copilot/config** - User preferences:
+```json
+{
+  "log_level": "none|error|warning|info|debug|all|default",
+  "show_banner": boolean,
+  "screen_reader": boolean,
+  "model": "string"
+}
+```
+
+**~/.copilot/mcp-config.json** - MCP server configuration:
+```json
+{
+  "mcpServers": {
+    "server-name": {
+      "command": "command-string",
+      "env": {
+        "VAR_NAME": "${REFERENCE}"
+      }
+    }
+  }
+}
+```
+
+**~/.copilot/agents/** - Custom agent definitions
+**.github/agents/** - Repository-level agents (v0.0.353+)
+
+### Slash Commands
+
+Internal commands use `/` prefix:
+- `/login` - Authentication
+- `/model [model]` - Model selection (Sonnet 4.5, Sonnet 4, Haiku 4.5, GPT-5)
+- `/mcp add|list|remove` - MCP server management
+- `/cwd [path]` - Change working directory
+- `/clear` - Clear session
+- `/usage` - Usage statistics
+- `/terminal-setup` - Configure terminal
+- `/feedback` - Submit feedback
+- `/user list|show|switch` - User management
+- `/agent <agent>` - Invoke custom agent (v0.0.353+)
+- `/delegate` - Async task delegation (creates PR, v0.0.353+)
+- `/exit`, `/quit` - Exit CLI
+
+### Authentication
+
+Multiple methods (in order of precedence):
+1. OAuth Device Flow (primary)
+2. Personal Access Token via `GH_TOKEN` or `GITHUB_TOKEN`
+3. GitHub CLI (`gh`) authentication
+4. GitHub Enterprise via `GH_HOST` environment variable
+
+### Key Features
+
+**Input Patterns:**
+- Natural language prompts
+- `@file.png` - Include files/images in context
+- `!command` - Direct shell execution
+- Multi-line input support (Kitty protocol)
+
+**Session Management:**
+- Persistent sessions with resume (`--resume`, `--continue`)
+- Session state: `~/.copilot/session-state/`
+- Timeline-based conversation UI
+
+**Advanced Capabilities:**
+- Parallel tool execution (v0.0.349+)
+- Async task delegation (v0.0.353+)
+- Token-by-token streaming (v0.0.348+)
+- Image support via @-mentions (v0.0.333+)
+- Custom agents (v0.0.353+)
+
+## 🔧 Working with This Repository
+
+### Issue Management
+
+**Automated Workflows:**
+- New issues auto-labeled as "triage"
+- Single-word issues auto-closed
+- Stale issues closed after 365 days
+- Feature requests get acknowledgment comment
+- "More info needed" workflow
+- "Unable to reproduce" handling
+
+**When Helping with Issues:**
+1. Check if it's a duplicate (search existing issues)
+2. Verify it's about the Copilot CLI (not VS Code, GitHub.com, etc.)
+3. Request minimal reproducible examples
+4. Reference changelog.md for version-specific behavior
+5. Note platform differences (Windows vs Linux vs macOS)
+6. Check if it's resolved in newer versions
+
+### Documentation Updates
+
+**README.md:**
+- Installation and prerequisites
+- Quick start guide
+- Feature overview
+- Links to official docs
+
+**changelog.md:**
+- Most detailed source of product information
+- Documents every release (v0.0.X format)
+- Contains architectural decisions and breaking changes
+- Reference this for historical context
+
+### Pull Requests for This Repo
+
+When creating PRs for documentation:
+1. Update README.md for user-facing changes
+2. Keep changelog.md accurate (typically maintained by maintainers)
+3. Ensure cross-platform accuracy (Windows paths, shell syntax)
+4. Link to related issues
+5. Preview markdown rendering
+
+## 📝 Conventions for AI Assistants
+
+### When Working with Issues
+
+**DO:**
+- Read the full issue and all comments before responding
+- Check changelog.md for relevant version information
+- Ask clarifying questions if the issue is vague
+- Provide workarounds while bugs are being fixed
+- Reference specific versions (e.g., "fixed in v0.0.350")
+- Consider cross-platform implications
+- Link to official documentation when relevant
+
+**DON'T:**
+- Make promises about implementation timelines
+- Attempt to access or modify source code (it's not here)
+- Assume features without checking changelog
+- Provide solutions that bypass security/permission systems
+- Recommend outdated installation methods
+
+### When Explaining the Product
+
+**Key Points to Emphasize:**
+1. **Preview-First:** All actions require user confirmation
+2. **Terminal-Native:** No context switching required
+3. **GitHub Integration:** Deep integration with GitHub services
+4. **Extensible:** MCP servers for custom tools
+5. **Cross-Platform:** Works on Linux, macOS, Windows
+6. **Agentic:** Plans and executes multi-step tasks
+7. **Premium Requests:** Each interaction counts toward quota
+
+### Common User Confusion Points
+
+**"It's not working":**
+- Check Node.js version (v22+ required)
+- Verify active Copilot subscription
+- Check organization/enterprise policy settings
+- Try `copilot --version` to verify installation
+- Check `~/.copilot/config` for log level
+
+**Authentication Issues:**
+- Order of precedence: OAuth > PAT > gh CLI
+- PAT needs "Copilot Requests" permission
+- GHE users need `GH_HOST` set
+- `/login` command for re-authentication
+
+**Permission Prompts:**
+- Expected behavior for security
+- Can use `--allow-tool` / `--deny-tool` flags
+- Can grant persistent path permissions
+- Smart heuristics added in v0.0.351
+
+**MCP Server Confusion:**
+- Default GitHub MCP server is bundled
+- Limited tool set by default (v0.0.350+)
+- Custom servers need `~/.copilot/mcp-config.json`
+- Check MCP server compatibility
+
+## 🚀 Development Workflow for This Repository
+
+### Branch Strategy
+
+- Main branch: Production documentation
+- Feature branches: For documentation updates
+- PR-based workflow with review
+
+### Git Commands
+
+When working with this repository:
+
+```bash
+# Check current branch
+git status
+
+# Create feature branch
+git checkout -b docs/update-description
+
+# Commit changes
+git add CLAUDE.md
+git commit -m "Add comprehensive CLAUDE.md for AI assistants"
+
+# Push to remote
+git push -u origin docs/update-description
+```
+
+### Commit Message Style
+
+Based on recent commits in changelog:
+- Clear, descriptive summaries
+- Reference specific features or fixes
+- Use present tense: "Add feature" not "Added feature"
+- Examples:
+  - "Update changelog for custom agents and /delegate command"
+  - "Fix formatting of changelog entry for clarity"
+  - "Update README with new authentication methods"
+
+## 📚 Reference Information
+
+### Key Files to Check
+
+1. **changelog.md** - Most comprehensive product information
+2. **README.md** - Installation and basic usage
+3. **.github/ISSUE_TEMPLATE/** - Valid issue formats
+4. **LICENSE.md** - Legal terms and restrictions
+
+### External Resources
+
+- [Official Documentation](https://docs.github.com/copilot/concepts/agents/about-copilot-cli)
+- [npm Package](https://www.npmjs.com/package/@github/copilot)
+- [Copilot Plans](https://github.com/features/copilot/plans)
+- [Model Context Protocol](https://modelcontextprotocol.io/)
+
+### Version History Highlights
+
+- **v0.0.353** - Custom agents, /delegate command for async tasks
+- **v0.0.350** - Limited GitHub MCP server tools by default, bundled dependencies
+- **v0.0.349** - Parallel tool execution
+- **v0.0.348** - Token-by-token streaming, bundled node-pty
+- **v0.0.342** - New session state format, GHE support via GH_HOST
+- **v0.0.333** - Image support via @-mentions, ! for shell execution
+- **v0.0.329** - Glob patterns for tool allow/deny rules
+
+## ⚠️ Important Reminders
+
+1. **This is NOT the source code repository** - Direct users to file issues, not to expect code changes here
+2. **Changelog is authoritative** - Use it as primary reference for features and behavior
+3. **Cross-platform considerations** - Windows behaves differently (PowerShell vs bash)
+4. **Subscription required** - Copilot subscription needed, premium requests tracked
+5. **Pre-release software** - Expect frequent updates and changes
+6. **Security model** - Permission system is fundamental, don't suggest bypasses
+7. **GitHub context** - Deeply integrated with GitHub, not a general-purpose CLI tool
+
+## 🎯 Quick Decision Tree for AI Assistants
+
+**User asks about installation/usage →** Reference README.md
+**User reports a bug →** Check if duplicate, ask for repro, reference changelog for version info
+**User asks about features →** Check changelog.md for feature availability and version
+**User has authentication issues →** Guide through auth methods in order of precedence
+**User wants to extend functionality →** Explain MCP servers and custom agents
+**User asks about source code →** Clarify this is docs repo, source is private
+**User asks about specific version behavior →** Reference changelog.md for that version
+**Documentation needs updating →** Create PR with clear description and rationale
+
+---
+
+**Last Updated:** 2025-12-04 (for repository state at commit 0d2c9de)
+**For Questions:** File an issue in this repository or check official documentation