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Documentation Index

Fetch the complete documentation index at: https://docs.fallow.tools/llms.txt

Use this file to discover all available pages before exploring further.

This page gets you from zero to a useful result fast. Everyone starts the same way. Branch off at the end.

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1. Run Fallow

From your project root: 
npx fallow
That runs three analyses in one pass:
  • Dead code: unused files, exports, dependencies, cycles, boundaries, and more
  • Duplication: repeated logic across files
  • Health: complexity hotspots and refactor targets
94 built-in plugins cover Next.js, Vite, Jest, Tailwind, PandaCSS, tap, tsd, and more. No configuration needed for the first run.

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2. Run the focused commands you’ll use most

npx fallow dead-code          # Cleanup candidates
npx fallow dupes              # Repeated logic
npx fallow health             # Complexity and refactor targets
npx fallow fix --dry-run      # Preview automatic cleanup

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3. Understand the output

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Dead code

Use this when you want cleanup candidates. 
npx fallow dead-code
Reports unused files, exports, types, dependencies, circular deps, and boundary violations. See the dead code guide.

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Duplication

Use this when repeated logic is spreading. 
npx fallow dupes
Default mild mode catches AST-based duplicates. Add --mode semantic to also catch clones with renamed variables. See the duplication guide.

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Health

Use this when you want to prioritize refactors. 
npx fallow health
Reports complexity findings, per-file maintainability, hotspots, and ranked refactor targets. See the health explanation.

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Fix preview

Use this before deleting anything automatically. 
npx fallow fix --dry-run
When you’re ready, drop --dry-run. See the auto-fix guide.

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4. Pick your next step

Existing repo with backlog? Read Adopt Fallow in an existing repo for a structured cleanup path, then come back here to wire up CI or VS Code.

Use it in VS Code

Real-time diagnostics, Code Lens above exports, and one-click fixes.

Use it in CI

Turn Fallow into a PR and merge gate with SARIF or MR annotations.

Use it from agents

Add MCP for structured tool calling from Claude Code, Cursor, and more.

Add runtime evidence

Layer production execution data into fallow health.

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Optional: create a config

Fallow works without a config file. When you want to customize, run: 
fallow init
This auto-detects your project structure and generates a tailored config. It also adds .fallow/ to your .gitignore. 
{
  "$schema": "https://raw.githubusercontent.com/fallow-rs/fallow/main/schema.json",
  "entry": ["src/workers/*.ts", "scripts/*.ts"],
  "ignorePatterns": ["**/*.generated.ts"],
  "rules": {
    "unused-files": "error",
    "unused-exports": "warn",
    "unused-types": "off"
  }
}
Migrating from knip or jscpd? Run fallow migrate, or see the knip or jscpd guides.

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Optional: runtime intelligence

Fallow’s static layer is free and open source. If you want to know what actually executed in production, add the runtime layer: 
npx fallow license activate --trial --email you@company.com
npx fallow coverage setup
npx fallow health --runtime-coverage ./coverage
Before you do that, read Static vs runtime intelligence for the mental model, then the runtime coverage guide for setup details.

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Optional: workflow-specific setup

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Agents

Any agent that can run a shell command can use Fallow. Use --format json for structured output: 
npx fallow --format json
npx fallow dead-code --format json
npx fallow fix --dry-run --format json
If your agent supports MCP, add structured tool calling: 
{
  "mcpServers": {
    "fallow": {
      "command": "fallow-mcp"
    }
  }
}
See the MCP integration guide.

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Humans

Install the VS Code extension for real-time diagnostics, Code Lens above exports, and one-click fixes: 
code --install-extension fallow-rs.fallow-vscode
See the VS Code integration guide.

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CI

Use the GitHub Action, the GitLab template, or npx fallow --ci on any CI: 
- uses: fallow-rs/fallow@v2
  with:
    format: sarif
See the CI integration guide.

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Next steps

Analysis overview

What Fallow analyzes, at a glance.

Configuration

Customize entry points, rules, and ignore patterns.

Explanations

Mental models for how Fallow works.

CLI reference

Every command and flag.