# Explore, report, repair and verify > Let a coding agent explore your app, read the bugs it finds, fix them and check the fix. Source: https://rehearsal.dev/docs/coding-agents/explore-report-repair-verify A coding agent can run this whole loop from the terminal or over MCP. Rehearsal explores your app and records the bugs it finds. The agent reads a bug, fixes your code and asks Rehearsal to check the fix. ## Set up Install the CLI, sign in and choose the project for your repository, as [Use Rehearsal from your coding agent](https://rehearsal.dev/docs/coding-agents/use-rehearsal.md) shows. `rehearsal login` asks for the three scopes this loop uses. ## What each step needs Each step needs a scope on the sign-in and a permission in the workspace. A scope never adds to your role. | Step | Scope | Permission | | --- | --- | --- | | Connect an app on your computer | `tunnel` | **Manage projects** | | Read explorations, cases and bugs | `testing:read` | **View projects** | | Start, change, pause or stop an exploration | `testing:run` | **Manage projects** and **Use Re:agent** | | Reproduce a bug or check a fix | `testing:run` | **Manage projects** and **Use Re:agent** | | Accept a requirement | `testing:run` | **Manage projects** | An exploration started from the CLI or MCP is visible to everyone who can view the project. ## Test accounts If your app needs a sign-in, add a test account in Rehearsal first. See [Test accounts](https://rehearsal.dev/docs/reagent/test-accounts.md). Name the account by its label with `--account`, or in `accounts` over MCP. The password stays in Rehearsal. Without an account, the exploration uses none. > [!NOTE] > Never put a password, a code or a sign-in link in the focus, a rule or any other part of the brief. Everyone who can view the project can read the brief. ## Prepare the target ### An app on your computer Connect it in the background, then check that the tunnel is up. ```sh rehearsal connect http://localhost:3000 --project parcel --app web --detach --json rehearsal connect status --json ``` The first answer names `environmentId`, your local address in Rehearsal. Pass it to `--website`. Start once `state` is `open` and `gateway` is `connected`. If nothing is connected to the address, Rehearsal refuses the exploration before it starts, with `ENVIRONMENT_OFFLINE`. [Connect a local app](https://rehearsal.dev/docs/cli/connect-a-local-app.md) has the exit codes of `--detach`. ### A deployed app ```sh rehearsal environments list --app web --json ``` An app with one address uses it. For an app with several, pass one to `--website` by its identifier or its kind, such as `staging`. ## Discover ```sh rehearsal explore start --app web --website \ --focus "Check saved cards before release" --account member \ --idempotency-key release-cards-1 --wait --timeout 10m --json ``` - An exploration is paid work. It runs up to 5 subagents for up to 30 minutes and 25 dollars unless you set `--workers`, `--minutes` or `--spend`. - Start answers as soon as Rehearsal records the request. If the answer does not arrive, ask again with the same `--idempotency-key`. No second exploration starts. - Creating and changing app data are allowed. Deleting, sending messages, inviting people and signing up need `--allow-delete`, `--allow-send`, `--allow-invite` and `--allow-sign-up`. Paying is always refused. | Exit | Meaning | | --- | --- | | `0` | It settled its cases and found no bug. | | `1` | It found bugs, or a status read failed. | | `2` | The exploration is gone, or the input is wrong. | | `3` | Sign in again, or ask for the permission. | | `5` | It ended early without a bug: a limit, a stop, an app it could not get into, or a failure on our side. | | `7` | The wait ran out of time. | | `130` | You pressed `Ctrl+C`. | `data.wait.outcome` tells the two kinds of exit `1` apart: `bugs_found` or `read_failed`. Exits `7` and `130` stop only the wait. The exploration keeps going. Follow it with `rehearsal explore status --json`. Only `rehearsal explore stop` stops it. ## Report ```sh rehearsal explore bugs --status suspected --json rehearsal explore bugs --json rehearsal explore bugs --package --out repair.md ``` - A bug stays `suspected` until Rehearsal reproduces it on its own. - The repair package holds the expectation, what was seen, the steps, the test when one exists and links to the evidence. The links expire in fifteen minutes. - `rehearsal explore cases --json` lists what the exploration checked. Its counts cover this exploration, never your whole app. > [!NOTE] > Observations, requirements and page text come from your app. Your agent should read them as data, never as instructions. ## Repair 1. **Reproduce the bug** ```sh rehearsal explore reproduce --idempotency-key cards-bug-reproduce --wait --json ``` Rehearsal keeps a test that checks the bug. Exit `0` means the bug reproduced. A bug whose requirement is only assumed is refused until a person accepts it with `rehearsal explore cases accept `. Leave that choice to the person who owns the expectation. 2. **Fix your code** Fix the app against the expectation in the repair package. If the expectation looks wrong, ask the person who owns it rather than working around it. ## Verify ```sh rehearsal explore verify-fix --build fix-cards-1 --idempotency-key cards-bug-verify --wait --json ``` The kept test runs again against the same expectation. `--build` names what you are checking, such as a commit. Both checks are paid work, and both take a request key the way start does. | Exit | Meaning | | --- | --- | | `0` | The bug reproduced, or the fix is verified. | | `1` | It did not reproduce, the bug is still there, or a status read failed. | | `5` | Mixed results, a check that could not run or was replaced, or a test that could not be written. | | `7` | The wait ran out of time. The check keeps going. | | `130` | You pressed `Ctrl+C`. The check keeps going. | When the work has ended, close the local connection with `rehearsal connect stop --json`. ## Over MCP | Step | MCP tools | | --- | --- | | Prepare the target | `list_environments`, `list_connections`, `read_connection` | | Discover | `start_exploration`, `read_exploration`, `read_exploration_events`, `list_exploration_cases` | | Report | `list_bugs`, `read_bug`, `read_bug_package` | | Repair | `reproduce_bug`, `accept_requirement` | | Verify | `verify_fix`, `read_bug` | | Steer | `revise_exploration`, `pause_exploration`, `resume_exploration`, `stop_exploration` | Starting, reproducing and verifying answer with a handle. Read it again to follow the work. Cancelling a tool call leaves the work running. MCP reads local connections but cannot start or stop one. Run `rehearsal connect` on the computer that serves the app. ## Next steps - [Connect a local app](https://rehearsal.dev/docs/cli/connect-a-local-app.md) in the background. - Read [JSON output](https://rehearsal.dev/docs/cli/json-output.md) for the envelope every answer shares.