skillforge

SkillForge

Deferred skill loading for Claude Code. Compress skills to stubs, load full content on demand.

Problem: Claude Code injects every skill's description into every system prompt turn. With 60+ skills, that's ~18k tokens of descriptions repeated on every message — context you're paying for but rarely using.

Solution: Replace verbose SKILL.md files with lightweight stubs (~35 tokens each). Full content loads only when a skill is actually invoked.

How It Works

When a compressed skill is invoked, Claude sees just this:

<!-- SKILLFORGE_COMPRESSED -->

IMPORTANT: Read the full skill before proceeding:
/Users/you/.claude/skills-full/everything-claude-code/api-design.md

That's 3-4 lines instead of the full 524-line skill. Claude reads the stub, follows the redirect, and loads the complete content on demand. One extra Read call per invocation — but since most turns trigger 0-1 skills, the savings are massive.

Token Economics

Metric	Before	After
Per-skill description	~300 tokens	~35 tokens
60 skills total	~18,000 tokens/turn	~2,100 tokens/turn
30-turn session	~540,000 tokens wasted	~63,000 tokens
Savings	—	~88% reduction

Install

/plugin
# Navigate to Marketplaces > jb-claude-plugins > Browse > skillforge
# Or if you have the marketplace: /plugin install skillforge@jb-claude-plugins

Usage

# See what's installed and compression status
/skillforge:status

# Compress all plugins
/skillforge:compress

# Compress a specific plugin
/skillforge:compress everything-claude-code

# Restore originals
/skillforge:restore

# Restore a specific plugin
/skillforge:restore everything-claude-code

Restart your Claude Code session after compress/restore for changes to take effect.

MCP Tools

SkillForge also provides an MCP server with two tools:

• load_skill(name) — Load full content of a compressed skill by name
• list_skills() — List all skills in the SkillForge vault

Important Notes

• Restart required after compress/restore (skill cache is per-session)
• Disable auto-update for compressed plugins — updates overwrite stubs
• Backups are safe — stored in ~/.claude/skills-full/, outside the plugin cache
• Idempotent — running compress twice skips already-compressed skills
• Non-destructive — restore brings back the original files from backup

Why This Exists

Claude Code's skill system injects all skill descriptions into the system prompt on every turn. There's no lazy-loading mechanism for skills (unlike deferred tools, which already support this pattern). We filed anthropics/claude-code#36023 requesting native deferred skill loading. SkillForge is the workaround until that ships.

License

MIT