Skip to main content

AI Agents

AI Agent integration has two parts:

  • The MCP server runs a real browser and exposes it as tools the agent can call: start a session, run Gherkin steps, take screenshots, read the DOM, evaluate JavaScript, investigate failures.
  • The skill is a context document that gives the agent deep knowledge of letsrunit. Without it, the agent can call the tools but won't know how to use them well.

Setup​

Install Letsrunit for your project, including the MCP server and skill

npx letsrunit@latest init

If you run init with no flags in an interactive terminal, the MCP option opens a second prompt where you can choose agents. For non-interactive mode find all available options with --help.

Global​

You can install the Letsrunit MCP server and skill globally for all your projects.

The Letsrunit plugin installs both the MCP server and the skill automatically. Run inside Claude Code:

/plugin marketplace add letsrunit-hq/agent
/plugin install letsrunit@letsrunit

AGENTS.md​

Add the following to your AGENTS.md or CLAUDE.md to instruct the agent to verify its work with letsrunit and store passing tests as regression tests:

The agent must write a browser test before marking the test as completed.

## Browser testing

Use letsrunit to verify any task that changes UI behaviour. A task is not complete until the relevant flow has been tested in a real browser and passes.

When a scenario passes:
- Save it as a `.feature` file under `/features`
- Include it in the commit
- These files run in CI as regression tests for future changes

Only keep scenarios that cover flows that could plausibly break from an unrelated change. Skip trivial or redundant ones.