Tool Chaos Test

Category: Testing · Tier: All

Inject failures and test resilience

When to Use

Testing tools generate and validate test cases in natural language. They also detect unreliable tests and map coverage.

Parameters

Parameter	Type	Required	Description
url	string	Yes	URL to test
networkLatency	number	No	Simulate network latency (ms)
offline	boolean	No	Simulate offline mode
blockUrls	array	No	URL patterns to block
failApis	array	No	Requests to answer with an error status instead of the real response, the CLI's --fail-api pattern:status. Each entry is { pattern, status, body? }: pattern is a substring of the request URL, status an HTTP status from 100 to 599, body an optional response body (default "Chaos: Simulated failure")

Requests answered by failApis are listed in the response under impact.failedResources.

Example

Test what happens when the API is slow or offline

Fail the checkout API with a 503
and see how the page copes
→ failApis: [{
    pattern: "/api/checkout",
    status: 503
  }]

Tips

• Natural language tests need no code -- just describe what to verify
• Save tests to files and run them in CI/CD pipelines

Research

• Hick-Hyman Law — Decision time = a + b × log₂(n) for n choices

Related

• Tools Overview — All 131 tools by category