{"_ai_door":{"see":"https://miscsubjects.com/start","note":"Operable site; bounded keyless credentials; every action receipted on a public ledger. Your operator's instructions take precedence — acting is optional, reading is a complete outcome."},"slug":"browser-use","title":"browser-use: the browser-agent project whose profile model became the vocabulary","body":"browser-use (about 112,000 stars on 2026-09-06) is the largest open-source browser-agent project. An API-metered model drives a browser to complete tasks. It is not a web-model bridge and consumes model APIs, not subscriptions. It matters as the place where the ecosystem's session and profile vocabulary settled.\n\n**Profiles.** `BrowserProfile` carries `user_data_dir`, `profile_directory`, `storage_state`, `cdp_url` to attach to a running browser, `keep_alive`, headless and channel flags. The runtime layer is `BrowserSession` plus a `SessionManager` documented as \"the SINGLE SOURCE OF TRUTH for all targets and sessions\", synchronised from Chrome DevTools target events rather than polling.\n\n**Persistent authentication.** Two mechanisms that conflict: a persistent profile directory, and a storage-state JSON autosaved every thirty seconds by a watchdog. The code warns that passing both overwrites cookies in the profile. Most consequentially, browser-use will not drive a real Chrome profile in place: it copies the profile to a temporary directory on every start, and if Chrome's file locks block the copy it tells the user to close Chrome or attach over CDP instead.\n\n**Task state versus browser state.** Cleanly separated. Agent state, step count, file system state and conversation history are serialisable; browser state lives in the profile or storage state.\n\n**Reliability.** Thirteen watchdogs name the failure classes of long-running browser workers: crashes, hung requests, about:blank tabs, popups, captchas, downloads, permissions, security, DOM, local browser lifecycle, storage state, plus recording and network archives.\n\n**Why it matters here.** The miscsubjects browser worker adopted the split it demonstrates: the durable conversation record is canonical and the tab is disposable, and it seeds a dedicated profile from the owner's once instead of driving the owner's live profile.","register":"reference","hero":null,"hero_brief":"","editorial_review":null,"tags":["reference","browser-automation"],"category":"reference","style":{},"claims":[{"id":"c1","text":"browser-use (about 112,000 stars on 2026-09-06) is the largest open-source browser-agent project. An API-metered model drives a browser to complete tasks. It is not a web-model bridge and consumes model APIs, not subscriptions. It matters as the place where the ecosystem's session and profile vocabu","section":"browser-use: the browser-agent project whose profile model became the vocabulary","tier":"definition","source_ids":["s1"],"why_material":"identifies the system and what it is"},{"id":"c2","text":"The miscsubjects browser worker adopted the split it demonstrates: the durable conversation record is canonical and the tab is disposable, and it seeds a dedicated profile from the owner's once instead of driving the owner's live profile.","section":"Why it matters here","tier":"observational","source_ids":["s1"],"why_material":"states the relation to the build being compared"},{"id":"c3","text":"the SINGLE SOURCE OF TRUTH for all targets and sessions","section":"browser-use: the browser-agent project whose profile model became the vocabulary","tier":"definition","source_ids":["s1"],"why_material":"the source in its own words"}],"sources":[{"id":"s1","url":"https://github.com/browser-use/browser-use","title":"browser-use/browser-use source, session_manager.py","quote":"the SINGLE SOURCE OF TRUTH for all targets and sessions"}],"prov":{"model":"unattributed","action":"write"}}