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Setup

1

Install our test library

npm install --save-dev magnitude-test
or see our demo repo if you don’t have a project to try it on
2

Initialize Magnitude

npx magnitude init
This will create a basic tests directory tests/magnitude with:
  • magnitude.config.ts: Magnitude test configuration file
  • example.mag.ts: An example test file
3

Configure LLM

The easiest way to set up an LLM for Magnitude is to set the ANTHROPIC_API_KEY environment variable. Sonnet 4 will be used by default. See LLM Configuration for more details.
🚀 Now you’re ready to run tests!

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Running tests

Run your Magnitude tests with: 
npx magnitude
This will run all Magnitude test files discovered with the *.mag.ts pattern. If the agent finds a problem with your app, it will tell you what happened and describe the bug!
To run many tests in parallel, add -w <workers>
To learn more about different options for running tests see here.

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Building test cases

Now that you’ve got Magnitude set up, you can create real test cases for your app. Here’s an example for a general idea: 
import { test } from 'magnitude-test';

test('can log in and create company', async (agent) => {
    await agent.act('Log in to the app', {
        data: { username: 'test-user@magnitude.run', password: 'test' }
    });
    await agent.check('Can see dashboard');
    await agent.act('Create a new company', { data: 'Make up the first 2 values and use defaults for the rest' });
    await agent.check('Company added successfully');
});
Acts, checks, and data are all natural language. Think of it like you’re describing how to test a particular flow to a co-worker - what steps they need to take, what they should check for, and what test data to use. For more information on how to build test cases see our docs.