Auto-Docs — Project Documentation for AI Agents

Generate and maintain structured project documentation optimized for AI coding agents. Creates documentation in multiple formats so every major AI tool can benefit:

The canonical source of truth is .ai/docs/ (rich TOON format with progressive disclosure). All other outputs are derived from it.

Three-Tier Progressive Disclosure

Modes

Generate Mode (default)

Creates documentation from scratch for a project. Use when:

• Running /auto-docs in a project with no .ai/docs/
• User says "generate project docs" or "document this project"

Update Mode

Updates existing documentation to match current code. Use when:

• Running /auto-docs update
• User says "update docs" or "refresh documentation"
• .ai/docs/ already exists

Generate Workflow

Phase 1: Discover

1. Read project manifest — look for package.json, Cargo.toml, go.mod, pyproject.toml, build.gradle, Makefile, docker-compose.yml, or similar
2. Map directory structure — use Glob to understand src/, lib/, app/, cmd/, etc.
3. Read existing docs — check README, AGENTS.md, CLAUDE.md, any existing documentation
4. Identify stack — language, framework, runtime, database, key libraries
5. Identify features — look for bounded domains: route groups, service directories, module folders. A "feature" = a user-facing capability or domain boundary (auth, payments, search), NOT a technical layer

Phase 2: Generate

Read the reference files before generating:

• references/toon-syntax.md — TOON format rules
• references/generation-templates.md — templates for each file type

Generate .ai/docs/ files in this order:

1. index.toon — feature catalog and doc links
2. overview.md — project summary and structure
3. Feature files (features/<name>.md) — one per identified feature
4. architecture.md — component map and data flow
5. decisions.md — key architectural decisions found in code/comments
6. dependencies.md — runtime, dev, and internal dependency maps

Rules:

• All file paths referenced in docs MUST exist in the project (verify with Glob)
• TOON [N] counts MUST match actual row counts
• Omit sections that don't apply (e.g., no routes table for a CLI tool)
• Be terse — abbreviate where meaning is clear
• Only document what you can verify from the codebase

Phase 3: Distribute

Generate tool-specific files from the .ai/docs/ content. Read references/generation-templates.md for the AGENTS.md template.

3a. AGENTS.md (universal — 20+ tools)

Create AGENTS.md at project root. This is the most important output — it's read by Codex, Gemini CLI, Jules, GitHub Copilot, Cursor, Windsurf, Aider, Roo Code, Kilo Code, Amp, OpenCode, and many more.

Content (standard Markdown, combine from .ai/docs/):

1. Project overview — from overview.md (what it does, stack, structure)
2. Commands — build, test, lint, dev commands from project manifest
3. Architecture — condensed from architecture.md (components, data flow, patterns)
4. Key Rules — conventions, constraints, patterns developers must follow
5. Features — table of features with file paths and descriptions

Keep under 4000 tokens — agents load this fully into context. Be terse.

3b. CLAUDE.md

Add the @ import to CLAUDE.md (create the file if needed):

## Project Documentation
@.ai/docs/index.toon

If CLAUDE.md already has content, add the import under a ## Project Documentation heading. Don't modify existing content.

3c. .cursor/rules/auto-docs.mdc

Create .cursor/rules/auto-docs.mdc with Cursor's MDC frontmatter format:

---
description: Project documentation generated by auto-docs
alwaysApply: true
---

<content from AGENTS.md>

3d. .github/copilot-instructions.md

Create .github/copilot-instructions.md (create .github/ dir if needed).

Content: same as AGENTS.md body. GitHub Copilot reads this file automatically in chat and inline completions.

Phase 4: Validate

Run the TOON validation script to catch syntax errors in all generated files.

First, ensure dependencies are installed (one-time):

npm install --prefix <skill-path>/scripts

Then validate:

node <skill-path>/scripts/validate.mjs .ai/docs

Where <skill-path> is the absolute path to this skill's directory (the folder containing this SKILL.md).

This validates:

• All .toon files (strict mode: array lengths, row counts, field consistency)
• All ```toon blocks embedded in .md files

If validation fails, fix the reported errors before proceeding. Common issues:

• [N] count doesn't match actual row count
• Mismatched column count in tabular array rows
• Unquoted values containing commas or colons

Phase 5: Report

Summarize what was generated:

• Number of features documented
• List of ALL files created, grouped by tool:
  • Universal: AGENTS.md
  • Canonical: .ai/docs/ (list files)
  • Claude Code: CLAUDE.md (with @ import)
  • Cursor: .cursor/rules/auto-docs.mdc
  • GitHub Copilot: .github/copilot-instructions.md
• Validation result (pass/fail with details)
• Any areas where documentation is incomplete (couldn't determine values)
• Suggestion to review and refine

Update Workflow

Phase 1: Diff Detection

1. Read current .ai/docs/index.toon to know what's documented
2. Scan the project for changes:
   • New directories/modules not in any feature file
   • New routes not documented
   • Deleted files still referenced in docs
   • New dependencies not in dependencies.md
   • Changed entry points or structure

Phase 2: Report Changes

Present a summary of detected changes:

Documentation drift detected:
- NEW: src/services/notifications/ (not documented)
- MOVED: src/auth/ → src/services/auth/ (path outdated in auth.md)
- REMOVED: src/legacy/ (still referenced in architecture.md)
- NEW DEP: @redis/client (not in dependencies.md)

Phase 3: Apply Updates

After user confirms (or if running non-interactively):

1. Update affected .ai/docs/ files
2. Update index.toon if features added/removed
3. Update [N] counts in all modified TOON blocks
4. Update the updated date in index.toon
5. Run validation: node <skill-path>/scripts/validate.mjs .ai/docs
6. Re-derive all tool-specific files — regenerate AGENTS.md, .cursor/rules/auto-docs.mdc, .github/copilot-instructions.md from updated .ai/docs/

Context Loading Guide

When working on a project with .ai/docs/, load files based on task:

TOON Quick Reference

key: value                              # simple key-value
parent:                                 # nested object
  child: value                          #   (indent 2 spaces)
parent.child: value                     # key folding (same as above)
items[3]{col1,col2}: ...               # tabular array header
  val1,val2                             #   row (indent 2 spaces)
tags[2]: a,b                            # primitive array
description: "has, commas"             # quote only if delimiters present

Full reference: references/toon-syntax.md Templates: references/generation-templates.md