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 skills add fallow-rs/fallow-skills --skill fallowgit clone --depth 1 https://github.com/fallow-rs/fallow-skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/fallow-rs/fallow-skills/fallow)<a href="https://agentmods.dev/skills/fallow-rs/fallow-skills/fallow"><img src="https://agentmods.dev/badge/skills/fallow-rs/fallow-skills/fallow/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/fallow-rs/fallow-skills/fallow"><img src="https://agentmods.dev/badge/skills/fallow-rs/fallow-skills/fallow.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
What 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 5.1 | $0.00114 | $0.08427 |
| Opus 5.5 | $0.00046 | $0.03371 |
| Sonnet 5.5 | $0.00023 | $0.01685 |
| Haiku 4.5 | $0.00011 | $0.00843 |
Grade A, and why
fallow 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 today.
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.
How it starts
The opening of the file, as written. The whole thing — 441 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Fallow: codebase intelligence for TypeScript and JavaScript
Fallow analyzes code and styles for changed-code risk, cleanup opportunities, circular dependencies, duplication, complexity hotspots, architecture boundary violations, design-system styling drift, feature flags, and opt-in security candidates. Runtime coverage merges production execution data into the same fallow health report for hot-path review and cold-path deletion confidence. A single local capture is available by default. Continuous or cloud runtime monitoring is optional.
When to Use
- Find cleanup opportunities: unused files, exports, types, members, dependencies, or feature flags that guard unused exports.
- Detect code duplication, circular dependencies, architecture boundary issues, and complexity hotspots.
- Find functions that may implement the same intent despite different names, syntax, or control flow (
fallow similar-code). - Check styling consistency, CSS dead surface, and design-token drift.
- Audit changed code before a commit, PR, release, or refactor.
- Set up CI quality gates, duplication thresholds, and regression baselines.
- Auto-fix supported unused exports and dependencies after
--dry-run. - Investigate why a specific export, dependency, file, or issue type was reported.
- Surface local security candidates for an agent to verify (
fallow security). - Find untested but runtime-reachable code (
fallow health --coverage-gaps). - Rank complexity hotspots, owners, and refactoring targets (
fallow health --hotspots --ownership --targets). - Review what fallow has surfaced over time (
fallow impact). - Confirm exact TypeScript symbol use, affected tests, API leaks, or public type coupling when syntactic evidence is insufficient (
--type-aware).
When NOT to Use
- Runtime error analysis or debugging
- Type checking (use
tscfor that). Type-aware fallow consumes checker evidence for project-wide analysis but does not report compiler diagnostics. - Linting style or formatting issues (use ESLint, Biome, Prettier)
- Verified security vulnerability scanning or SAST.
fallow securitysurfaces local, deterministic security candidates for a downstream agent to verify; it does not prove exploitability. Use Snyk, CodeQL, or Semgrep for verified scanning, and an SCA tool for dependency CVEs. - Bundle size analysis
- Projects that are not JavaScript or TypeScript
What ships with it
8 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- today Changed 409179a3dbf4
- 5d ago Changed c5d72f0cd7a0
- 10d ago Changed · +22 lines 151bedbae99f
- 21d ago Changed · +1 lines 25d680b5266c
- 22d ago Changed 5be0eaed060b
- 23d ago Changed · +3 lines d593b2c82f80
- 28d ago Changed · +18 lines bbd8e7e4df4b
- 29d ago Changed · +2 lines 46366a062e72
- 1mo ago Changed · +1 lines eea8e7785bc3
- 1mo ago First seen · 394 lines · 114 tokens per session scan A 8403d6fd4c4b
fallow is a skill published in the GitHub repository fallow-rs/fallow-skills (137 stars, last pushed today), licensed MIT. It adds 114 tokens to every session and 8,427 once invoked, about $0.0005 per session on Opus 5.5. 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.
Other skills, from other repositories
cmux-review
Review agent-written changes before merge, after substantial edits, or when re-reviewing a repair. Use the adversarial protocol for high-risk changes or an explicitly requested deep review.
code-review
Review a branch, PR, or worktree diff for repository conventions and stated intent.
pr
Write a fast-to-review pull request body with a visual summary, before/after evidence, and merge-risk analysis.
pr-review
Fix PR review comments by implementing requested changes.
slop
Remove AI-generated code slop from git diffs to maintain code quality.
code-quality-review
Audit a diff for structural maintainability and unnecessary complexity.