Start a test sign-in of a stored app login.

With every secret its sign-in method and header need saved, a machine that records captures opens the sealed login and signs in to the app headlessly, exactly as a recording would, then opens the app signed in and keeps one picture of what it saw. Answers at once with test.status: running; read the outcome with the GET. A test already running is answered as it is. Not a way to check logins for apps that are not yours: at most 5 tests an hour per person and 10 a day aimed at one app from all accounts (429 app_connection_test_limited), every test audit-logged, and for an app whose origin is not verified as yours the outcome is passed or failed and the picture, never why. A missing secret queues nothing (ready: false, missingSecrets). A running test can wait up to five minutes for a requested one-time code, entered only in that test on Connected apps. Story API, CLI, MCP and Slug never accept that code. mfa_required means that attempt ended without completing its second sign-in step. For an interactive retry, enter a requested code only in the running sign-in's temporary field. For unattended sign-in, save an authenticator setup key if the app accepts its codes, or use a saved session or capture grant. Sleeper cannot read email or texts, follow sign-in links, approve push requests, or use a passkey. Free and safe to repeat, so no Idempotency-Key. A form sign-in follows the app's sign-in steps (connection.signInRecipe): with none kept yet, Sleeper reads the signed-out app first (no login goes with that read) and checks the steps against the saved secrets before anything is typed; a step that no longer matches is repaired once. findSignIn: true finds the steps again first. A story project is refused with 409 project_not_product (nothing is stored or started): app connections are for product projects. Listing, reading and deleting a story project's existing connections still work.