✨ Add generate-llms-txt command for LLM site navigation

Create new slash command to generate llms.txt files following the
llmstxt.org specification. Command intelligently detects project type
and places file in appropriate location (public/, static/, or root).

Features:
- Auto-detects web framework and documentation structure
- Generates proper markdown format (H1, blockquote, sections)
- Organizes documentation links by priority
- Handles updates to existing files
- Follows llms.txt standard for helping LLMs navigate sites

Similar to generate-AGENTS-file but focused on external site navigation
rather than internal project context.

Author: claude

.claude/commands/generate-llms-txt.md

@@ -0,0 +1,253 @@
+---
+description: Generate or update llms.txt file to help LLMs understand and navigate your site
+---
+
+# Generate llms.txt
+
+Creates or updates `llms.txt` - a standardized file that helps Large Language Models understand and navigate your website or documentation at inference time.
+
+<philosophy>
+llms.txt provides LLM-friendly navigation and context for websites and documentation. It should be:
+- Concise - LLMs have limited context windows
+- Navigational - Links to key documentation rather than duplicating it
+- Structured - Uses markdown format for easy LLM parsing
+- Focused - Highlights most important resources first
+
+Think: "What does an LLM need to understand and effectively use this site?"
+</philosophy>
+
+<workflow>
+<determine-location>
+Detect the appropriate location for llms.txt based on project type:
+
+1. Check for `public/` directory (Next.js, React, Vue, many static site generators)
+2. Check for `static/` directory (Django, Flask, Hugo)
+3. Check for `docs/` directory if this appears to be a documentation site
+4. Default to repository root if none found
+
+The file should be placed where it will be accessible at the URL path `/llms.txt` when the site is deployed.
+</determine-location>
+
+<analyze-project>
+Understand the project structure to generate relevant content:
+
+1. Detect project type:
+   - Check `package.json` for web frameworks (Next.js, React, Vue, etc.)
+   - Check `pyproject.toml`, `requirements.txt` for Python frameworks (Django, Flask, FastAPI)
+   - Check for static site generators (Hugo, Jekyll, Gatsby, etc.)
+   - Check for documentation tools (MkDocs, Docusaurus, VitePress, etc.)
+
+2. Identify key documentation:
+   - Look for README.md
+   - Look for docs/ or documentation/ directory
+   - Look for CONTRIBUTING.md, ARCHITECTURE.md, API.md
+   - Check .cursor/rules/ for coding standards
+   - Check .claude/agents/ for specialized agents
+   - Check for API documentation (OpenAPI/Swagger files)
+
+3. Identify important links:
+   - GitHub repository URL (from package.json, git remote)
+   - Documentation site URL (from package.json, README)
+   - API reference locations
+   - Getting started guides
+</analyze-project>
+
+<generate-structure>
+Create llms.txt following the standard format:
+
+```markdown
+# Project Name
+
+> Brief 1-2 sentence description of what this project/site is and what it helps users accomplish.
+
+Additional context paragraph (optional): More detailed information about the project's purpose, key features, or important background that helps LLMs understand how to use the site effectively.
+
+## Documentation
+
+- [Getting Started](url): Brief description of what this covers
+- [Core Concepts](url): Brief description
+- [API Reference](url): Brief description
+
+## Guides
+
+- [Guide Title](url): Brief description
+- [Another Guide](url): Brief description
+
+## Reference
+
+- [Configuration](url): Brief description
+- [CLI Commands](url): Brief description
+- [Architecture](url): Brief description
+
+## Optional
+
+- [Less Critical Resource](url): Brief description
+- [Advanced Topics](url): Brief description
+```
+
+Structure guidelines:
+- **H1 title** (required): Project or site name
+- **Blockquote** (recommended): Short summary with key information for understanding the rest of the file
+- **Additional context** (optional): Detailed background if needed
+- **Sections** (H2 headers): Organize documentation by category
+  - Common categories: Documentation, Guides, Reference, API, Examples, Contributing
+  - Use "Optional" section for less critical resources
+- **Links**: Markdown format with optional brief descriptions
+  - Use relative paths for internal documentation
+  - Use absolute URLs for external resources
+  - Keep descriptions concise
+
+Priority order:
+1. Getting started / quickstart guides
+2. Core concepts and tutorials
+3. API reference and technical documentation
+4. Advanced topics and edge cases
+5. Contributing and community resources
+</generate-structure>
+
+<create-llms-full-txt>
+Optionally create llms-full.txt alongside llms.txt:
+
+- `llms.txt` - Lightweight navigation file (links to docs)
+- `llms-full.txt` - Comprehensive file with full documentation content
+
+For most projects, start with just `llms.txt`. Only create `llms-full.txt` if:
+- Project has extensive documentation that would benefit from a single-file view
+- Documentation is already in markdown format
+- Total size would be reasonable (< 100KB)
+
+Skip llms-full.txt creation for now unless user specifically requests it.
+</create-llms-full-txt>
+
+<optimize-for-llms>
+Review and optimize the generated content:
+
+1. **Prioritize ruthlessly**: Most important links first
+2. **Be concise**: Brief descriptions, not full explanations
+3. **Use relative paths**: For internal documentation (easier to maintain)
+4. **Organize logically**: Group related topics together
+5. **Mark optional content**: Use "Optional" section for nice-to-have resources
+6. **Keep it current**: Link to actively maintained documentation
+7. **Test URLs**: Ensure all links will be valid when deployed
+
+Target: Under 2KB for most projects (focused navigation, not content duplication)
+</optimize-for-llms>
+
+<report>
+Show the user:
+1. Where the file will be created (with explanation of why)
+2. The generated content
+3. File size
+4. Suggestions for what to add if content seems sparse
+5. Next steps (how to verify it works, how to update it)
+</report>
+</workflow>
+
+<update-mode>
+When `llms.txt` already exists:
+
+1. Read existing file to understand current content
+2. Analyze project for changes:
+   - New documentation files added
+   - Changed project structure
+   - Updated README or documentation
+   - New major features or guides
+3. Suggest additions or updates with rationale
+4. Show diff of proposed changes
+5. Let user review before updating
+
+Preserve existing structure and organization unless there's a good reason to change it.
+</update-mode>
+
+<key-principles>
+Navigation over duplication: Link to documentation, don't duplicate it.
+
+LLM-friendly format: Markdown is the most widely understood format for LLMs.
+
+Prioritize ruthlessly: LLMs have limited context - put most important content first.
+
+Keep it current: Outdated links are worse than missing links.
+
+Test the result: After generating, consider "Would an LLM understand how to navigate this site?"
+</key-principles>
+
+<location-detection-examples>
+Example directory structures and where to place llms.txt:
+
+Next.js project:
+```
+project/
+├── public/ ← Place llms.txt here
+├── src/
+└── package.json
+```
+
+Django project:
+```
+project/
+├── static/ ← Place llms.txt here
+├── myapp/
+└── manage.py
+```
+
+Documentation site:
+```
+project/
+├── docs/ ← Consider placing here if this is the deployed location
+├── README.md
+└── mkdocs.yml
+```
+
+Plain repository (no public/static):
+```
+project/
+├── llms.txt ← Place in root
+├── README.md
+└── src/
+```
+</location-detection-examples>
+
+<common-sections>
+Recommended section organization based on project type:
+
+**API/Library Project:**
+- Documentation (getting started, core concepts)
+- API Reference
+- Examples
+- Guides
+- Optional (advanced topics, contributing)
+
+**Web Application:**
+- Documentation (overview, quickstart)
+- User Guides
+- API Documentation (if applicable)
+- Architecture
+- Optional (deployment, troubleshooting)
+
+**Documentation Site:**
+- Getting Started
+- Tutorials
+- Reference
+- Guides
+- Optional (FAQ, community)
+
+**Developer Tool/CLI:**
+- Documentation (installation, quickstart)
+- Commands Reference
+- Configuration
+- Examples
+- Optional (plugins, advanced usage)
+</common-sections>
+
+<final-checklist>
+- File location is appropriate for project type
+- H1 title reflects project name
+- Blockquote provides clear project summary
+- Sections are logically organized
+- Most important links come first
+- "Optional" section for less critical resources
+- Link descriptions are concise and helpful
+- All URLs will be valid when site is deployed
+- File is under 2KB (focused navigation)
+- Format follows llms.txt specification from llmstxt.org
+</final-checklist>