fallow

fallow is a skill for Claude Code, Codex from travisennis/acai. It costs 40 tokens per session (1,613 once invoked), scanned A, original, MIT.

A static analysis tool for JavaScript and TypeScript code. Static analysis examines code without running it to find unused code, repeated code, complex areas, and broken architecture boundaries.

In plain words
What is it for?
Use it after editing or generating code, before committing, or when cleaning up dead code and reducing complexity.
Why use it?
It reveals project-wide problems that file-by-file checks can miss, such as unused exports, unreferenced files, circular dependencies, and cross-file duplication.

Skill for Claude CodeCodex

Install

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.

agentmods
npx agentmods add skills/travisennis/acai/fallow
Any agent
npx skills add travisennis/acai --skill fallow
Clone the repo
git clone --depth 1 https://github.com/travisennis/acai

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for fallow

README.md
[![agentmods](https://agentmods.dev/badge/skills/travisennis/acai/fallow.svg)](https://agentmods.dev/skills/travisennis/acai/fallow)
Your own site
<a href="https://agentmods.dev/skills/travisennis/acai/fallow"><img src="https://agentmods.dev/badge/skills/travisennis/acai/fallow.svg" alt="Measured on agentmods" height="20"></a>
Per session 40 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,613 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00040 $0.01613
Opus 5 $0.00020 $0.00807
Sonnet 5 $0.00008 $0.00323
Haiku 4.5 $0.00004 $0.00161

Measured 3d ago against content hash 3dad2132ba9b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

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 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.

.agents/skills/fallow/SKILL.md · 197 lines

How it starts

The opening of the file, as written. The whole thing — 197 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Fallow

Fallow is a Rust-native static analysis tool for TypeScript and JavaScript that finds dead code, duplication, complexity hotspots, and architecture boundary violations. It builds a project-wide module graph, so it catches problems file-local tools cannot: unused exports, files nothing imports, circular dependencies, cross-file duplicate blocks, and boundary violations.

Run fallow after generating or editing code to review the impact, before committing to catch regressions, or when asked to clean up dead code or reduce complexity.

Quick Reference

npx fallow                      # Full analysis: dead code + duplication + health
npx fallow dead-code            # Dead code only
npx fallow dupes                # Duplication only
npx fallow health               # Complexity and health score
npx fallow audit                # Audit changed files (PR gate)
npx fallow fix --dry-run        # Preview automatic cleanup
npx fallow --format json        # Structured output with per-issue actions
npx fallow --summary            # Category counts only

When to Run Fallow

After generating or editing code:

npx fallow --summary

Before committing (audit changed files):

npx fallow audit --base main --format json

When asked to clean up or reduce complexity:

npx fallow --format json
npx fallow health --top 20       # 20 most complex functions
npx fallow dead-code             # See what can be removed

Key Commands

Dead Code

Finds unused files, exports, types, dependencies, enum members, class members, circular dependencies, boundary violations, and stale suppressions.

npx fallow dead-code
npx fallow dead-code --unused-exports         # Only unused exports
npx fallow dead-code --circular-deps          # Only circular dependencies
npx fallow dead-code --production             # Exclude test/dev files
npx fallow dead-code --changed-since main     # Only files changed vs main
npx fallow dead-code --group-by owner         # Group by CODEOWNERS

Read the full file on GitHub · 197 lines

Changes

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.

  1. 3d ago First seen · 197 lines · 40 tokens per session scan A 3dad2132ba9b

Subscribe to this mod's changes

fallow is a skill published in the GitHub repository travisennis/acai (5 stars, last pushed 1mo ago), licensed MIT. It adds 40 tokens to every session and 1,613 once invoked, about $0.0002 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 2026-08-31.

Related

Other skills, from other repositories

systematic-debugging

Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.

obra/superpowers · 21 tokens

brainstorming

You MUST use this before any creative work - creating features, building components, adding functionality, or modifying behavior. Explores user intent, requirements and design before implementation.

obra/superpowers · 37 tokens

auto-perf-optimize

Run agent-driven VS Code performance or memory investigations. Use when asked to launch Code OSS, automate a VS Code scenario, run the Chat memory smoke runner, capture renderer heap snapshots, take workflow screenshots, compare run summaries, or drive a repeatable scenario before heap-snapshot analysis.

microsoft/vscode · 62 tokens

chat-perf

Run chat perf benchmarks and memory leak checks against the local dev build or any published VS Code version. Use when investigating chat rendering regressions, validating perf-sensitive changes to chat UI, or checking for memory leaks in the chat response pipeline.

microsoft/vscode · 51 tokens

chat-pet-sprite-creation

Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.

microsoft/vscode · 53 tokens

cpu-profile-analysis

Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…

microsoft/vscode · 71 tokens