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Documentation Index

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The Cruel CLI provides a powerful command-line interface for chaos testing your APIs and services. Run tests, benchmarks, and predefined scenarios directly from your terminal.

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Installation

Install Cruel globally to use the CLI: 
npm install -g cruel
Or run directly with npx: 
npx cruel test https://api.example.com

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Quick Start

# Test an endpoint with 10% failure rate
cruel test https://api.example.com --fail 0.1 --count 20

# Benchmark endpoint performance
cruel benchmark https://api.example.com --count 100 --concurrent 10

# Run a chaos scenario
cruel scenario outage --duration 5000

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Available Commands

test

Test endpoints with chaos injection

benchmark

Benchmark endpoint performance

scenarios

Run predefined chaos scenarios

stats

View chaos testing statistics

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Global Options

These options work across all commands:
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--fail
number
Failure rate between 0 and 1 (e.g., 0.1 = 10% failure rate)
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--delay
number | string
Delay in milliseconds or min-max range (e.g., 100 or “100-500”)
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--timeout
number
Timeout rate between 0 and 1 (e.g., 0.05 = 5% timeout rate)
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--preset
string
Use a predefined chaos configuration presetAvailable presets: development, staging, production, harsh, nightmare, apocalypse
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--retry
number
Number of retry attempts for failed requests
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--circuit
number
Circuit breaker failure threshold before opening circuit

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Chaos Presets

Cruel includes several built-in presets for different testing scenarios: 
# View all available presets
cruel presets
Available Presets:
  • development - Light chaos for local development
  • staging - Moderate chaos for staging environments
  • production - Realistic production chaos patterns
  • harsh - High chaos for stress testing
  • nightmare - Extreme chaos conditions
  • apocalypse - Maximum chaos for worst-case scenarios

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Usage Examples

cruel test https://api.example.com --preset nightmare

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Output Format

The CLI provides visual feedback with colored output:
  • . - Successful request (green)
  • X - Failed request (red)
  • T - Timed out request (yellow)

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Statistics

View accumulated chaos statistics: 
cruel stats
This shows:
  • Total calls made
  • Number of failures injected
  • Number of timeouts
  • Number of delays
  • Corrupted responses
  • Rate limited requests
  • Streams cut

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Version

Check your Cruel version: 
cruel version
# or
cruel --version
cruel -v

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Help

Get help on any command: 
cruel help
# or
cruel --help
cruel -h

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