---
title: "Create Tests"
description: "Author tests with your coding agent: YAML E2E tests, agent verifications that prove the backend behind a journey, and comprehensive coverage for a feature or PR, all via /shiplight."
---

# Create Tests

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Authoring tests is the main Shiplight workflow, all through `/shiplight`. Your agent writes YAML tests for most flows. For a whole feature or PR, a **coverage** pass decides what to test and drives it for you.

## YAML tests

Run `/shiplight create-yaml-tests` for fast, replayable YAML E2E tests: the agent walks your app in a real browser and captures real locators.

```
/shiplight create-yaml-tests for the sign-up flow at http://localhost:3000 —
a new user should register, verify their email, and land on the dashboard
```

It assumes the project is already scaffolded. Run `/shiplight init` first on a new project, and see [Authentication](/local/agent-workflow/authentication) for the authenticated flow. It doesn't invent YAML: it explores the UI, captures locators, writes focused tests (one journey each), and validates them before finishing. On an existing project it reads your specs and tests first. It also handles updates:

```
/shiplight create-yaml-tests add a test for the "forgot password" flow
```

See the [YAML Test Format](/local/yaml-tests/) chapter for the format.

::: tip Need something more flexible than a YAML test?
For core journeys that must not ship broken, run **`/shiplight create-agent-verification`** — the most comprehensive format, driving the journey through the UI and then proving the backend state it should have changed (API, DB, logs). A coding agent executes the Markdown case against a live environment and returns an auditable status report. See [Agent Verification](/local/agent-verification).
:::

## Comprehensive coverage

For a whole feature or PR, **`/shiplight cover`** decides _what_ must be tested and _how_, then drives the producers to write it — a YAML test, an agent verification, or your project's own unit / contract / integration test — spending the expensive test budget (e2e, agent) where priority is highest and using the cheapest modality that can actually prove each check.

```
/shiplight cover the billing feature on this PR
```

It records the result as facts, not a graded verdict:

| Artifact                         | What it holds                                                              |
| -------------------------------- | -------------------------------------------------------------------------- |
| `specs/<feature>/test-spec.md`   | The behaviors and invariants to verify, each with its priority             |
| `specs/<feature>/test-report.md` | What was tested, by what test type, and what passed / failed / was blocked |
| `TESTING.md` (optional)          | Project-wide testing posture (a baked-in default applies when absent)      |