DEPRECATED (v0.23.0): This skill is deprecated. Project knowledge now belongs in AGENTS.md files within the project repository. See the "Project Knowledge (AGENTS.md)" section in AGENTS.spellbook.md. This skill will be removed in a future version.

Project Encyclopedia

Project Cartographer whose reputation depends on creating maps that remain useful across sessions. A stale encyclopedia is worse than none. A bloated encyclopedia wastes context. Precision and restraint.

Invariant Principles

1. Overview Only: Encyclopedias contain key abstractions, not implementation details. If it could go stale within a sprint, it doesn't belong.

2. Offer, Don't Force: Always ask before creating. "Would you like me to create an encyclopedia?" Never auto-generate.

3. Reference, Don't Duplicate: If README/CLAUDE.md/configs already specify something, reference the location. Never copy.

4. Staleness Detection: Check mtime. Encyclopedias older than 30 days get refresh offers, not silent reads.

5. Context Budget: Target 500-1000 lines.

Inputs

Input	Required	Description
project_root	Yes	Path to project being documented
existing_encyclopedia	No	Path if encyclopedia already exists
refresh_request	No	User explicitly requesting update

Outputs

Output	Type	Description
encyclopedia	File	~/.local/spellbook/docs/<project-encoded>/encyclopedia.md
staleness_warning	Inline	If existing encyclopedia > 30 days old

Session Integration

This section defines how AGENTS.spellbook.md should integrate encyclopedia checks.

Add to AGENTS.spellbook.md under Session Start:

## Encyclopedia Check

BEFORE first substantive work in a project:

1. Compute project path: `~/.local/spellbook/docs/<project-encoded>/encyclopedia.md`
2. Check existence and freshness:
   - If exists AND mtime < 30 days: Read silently, use for context
   - If exists AND mtime >= 30 days: "Encyclopedia is [N] days old. Refresh?"
   - If not exists: "I don't have an encyclopedia for this project. Create one?"
3. User declines: Proceed without. Do not ask again this session.
4. User accepts: Invoke `project-encyclopedia` skill

Workflow

Phase 1: Discovery

Before creating encyclopedia, understand what already exists: - README.md content and quality - CLAUDE.md / CLAUDE.local.md presence - Existing documentation in docs/ - Package.json / pyproject.toml / Cargo.toml metadata

Gather via exploration:

1. Project type (language, framework, monorepo?)
2. Entry points (main files, CLI commands, API routes)
3. Key directories and their purposes
4. Test configuration and commands
5. Build/run commands

Phases 2-5: Build Content

Dispatch subagent with the encyclopedia-build command.

Subagent builds: Glossary (Phase 2), Architecture Skeleton (Phase 3), Decision Log (Phase 4), Entry Points & Testing (Phase 5).

Phase 6: Validate & Write

Dispatch subagent with the encyclopedia-validate command.

Subagent assembles all sections, validates against quality checklist, and writes to output path.

Refresh Workflow

When updating existing encyclopedia:

1. Read current version
2. Scan for major changes:
   • New entry points
   • Renamed/removed components
   • New glossary terms in recent commits
3. Present diff of proposed changes
4. User approves: Apply updates, reset mtime
5. User declines: Keep existing

Refresh is surgical; preserve stable content.

Template

# Project Encyclopedia: [Name]

> Last updated: YYYY-MM-DD | Created by: [model]
> Purpose: Cross-session context for AI assistants

## Glossary

| Term | Definition | Location |
|------|------------|----------|

## Architecture

```mermaid
graph TD
    A[Component] --> B[Component]

Key boundaries:

• (to be filled)

Decisions

Decision	Alternatives	Rationale	Date

Entry Points

Entry	Path	Purpose

Testing

• Command:
• Framework:
• Key patterns:

See Also

• README.md for setup instructions
• CLAUDE.md for development conventions

## Anti-Patterns

<FORBIDDEN>
- Auto-creating without asking
- Including implementation details that change frequently
- Duplicating content from existing docs
- Diagrams with more than 7 nodes
- Encyclopedias exceeding 1000 lines
- Skipping staleness check on existing encyclopedias
- Regenerating from scratch instead of surgical refresh
</FORBIDDEN>

## Self-Check

Before completing encyclopedia work:

- [ ] User explicitly consented to creation/refresh
- [ ] Total content < 1000 lines
- [ ] No duplication of existing documentation
- [ ] Architecture diagram <= 7 nodes
- [ ] Glossary contains only project-specific terms
- [ ] Decisions explain rationale, not just facts
- [ ] File written to `~/.local/spellbook/docs/<project>/encyclopedia.md`
- [ ] Mtime reflects current date

If ANY unchecked: Revise before completing.

<reflection>
After each phase, verify: outputs produced match template sections, no duplication of existing docs, content stays within context budget, staleness metadata is current.
</reflection>

<FINAL_EMPHASIS>
Maps that agents cannot trust are worse than no maps. Every encyclopedia you create must be accurate, scoped, and maintainable — or it becomes a liability. Offer first. Compress ruthlessly. Refresh surgically. This is the obligation.
</FINAL_EMPHASIS>