Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add instructions/tessro/fab/claude-mdgit clone --depth 1 https://github.com/tessro/fabWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00299 | $0.00299 |
| Opus 5 | $0.00150 | $0.00150 |
| Sonnet 5 | $0.00060 | $0.00060 |
| Haiku 4.5 | $0.00030 | $0.00030 |
Grade A, and why
fab CLAUDE.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
fab - Claude Code Instructions
Branding
Use the bus emoji 🚌 to brand the project:
- README.md header
- CLI output (e.g.,
🚌 fab daemon started) - TUI header
- Error messages where appropriate
Project Context
fab is a coding agent supervisor - it manages multiple Claude Code instances across projects with automatic task orchestration via ticket (tk).
Code Style
- Go 1.25
- Use standard Go project layout (cmd/, internal/)
- Prefer simplicity over abstraction
- Error messages should be actionable
Commits
- Atomic commits: One logical change per commit
- Conventional commits:
type(scope): message- Types:
feat,fix,docs,chore,refactor,test - Scope: optional, e.g.,
cli,tui,daemon,ticket
- Types:
- Keep subject line under 72 chars
- Reference issue IDs in body when applicable
- Push after committing - don't let commits pile up locally
Releases
- Releases are CI-driven via GitHub Actions on
vX.Y.Ztags - Do not use
gh releasemanually
Key Conventions
- Config lives in
~/.config/fab/config.toml - Daemon socket at
~/.fab/fab.sock - Worktrees in
~/.fab/worktrees/<project>/
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 3d ago First seen · 42 lines · 299 tokens per session scan A 410acac06ad3
fab CLAUDE.md is an instructions file published in the GitHub repository tessro/fab (23 stars, last pushed 7mo ago), licensed MIT. It adds 299 tokens to every session, about $0.0015 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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