A REAL CLOUD BROWSER FOR A TASK ON A WEBSITE: the user's own signed-in account (email, social, shop, bank or work portal, through a persona_id from writ_personas: the password stays sealed in Writ, and sessions never ask for a password), a click, form, submit, search inside an app, setting change, booking or post, or a page a plain fetch cannot open (login wall, 403, CAPTCHA). OPENS a real cloud browser and returns the first live page observation. It is not an autonomous agent: Writ runs no model here, the caller is the brain and the driver, and each writ_browser_act(session_id) batch performs exactly the actions it is given. One call opens one browser for one task and performs no step itself. RECORDING IS ALWAYS ON, saving is on demand: every interaction in the session is recorded. A task recorded for reuse carries each value that changes as {{name}} with its real value in writ_browser_act inputs, and its data leaves through an extract action; writ_browser_save(name) then answers with the steps, inputs and a run_example, and the workflow replays at zero AI cost (writ_run_workflow). writ_browser_cancel closes an unsaved session; an open browser bills until it is closed. In the session: navigate, click, fill, type, select, press keys, scroll, switch tabs, upload a file, sign in (a persona's 2FA code is minted server-side); see the page (read_text, get_dom for the real HTML, inspect a selector, list_candidates for repeating rows, get_screenshot); read every backend call the page makes (capture_network, then search/read them with writ_browser_network); run any JavaScript on the live page (evaluate_js) and call the site's backend from inside the session with its cookies (api_call); work a page whose content only appears after interaction. NOT FOR: reading a page, a few pages, or the top N items of a listing (writ_scrape: one call, 2-10s, no browser); collecting a site into a dataset (writ_crawl_site); turning a site into an API (writ_website_to_api, which opens the same browser bound to a build). A browser costs execution time for as long as it is open.

The page comes back after every batch and on demand via writ_browser_context(section=page). A sensitive fill carries data_key: the value is held server-side and the saved step keeps a placeholder, never the raw value. writ_browser_compose adds what the recorder cannot see (named functions, explicit steps, an input's description/default). A saved workflow replays the same task without a browser (writ_list_workflows -> writ_run_workflow); the first observation lists this site's matching ones in saved_for_this_site. A browser's exit IP is fixed once it opens: past a bot wall or CAPTCHA, a new session with use_residential=true exits residential (writ_browser_cancel closes the blocked one). writ_browser_sessions lists open sessions; an open one is warm and cheaper to continue than a new one.