Open Browser Use

Overview

Open Browser Use connects an MV3 Chrome extension, a local native messaging host, a CLI, SDKs, and an optional stdio MCP server so agents can automate a real Chrome profile. It is not Codex.app-specific; adapt the commands, MCP config, and SDK examples to the agent runtime you are operating in.

Core Workflow

1. Check setup with open-browser-use ping or obu ping. If it fails because setup is missing, read references/installation.md.
2. Pick the right Chrome profile if multiple are installed. See "Multi-profile handling" below before issuing browser commands.
3. Choose a unique browser session id for the current agent task before opening or claiming tabs. Prefer the surrounding runtime's conversation/session id when available; otherwise create a short unique id such as obu-\x3Ctask-slug>-\x3Ctimestamp>. Reuse that same id for every Open Browser Use command in this task.
4. Name the current browser task group before opening or claiming tabs. Use a short task label followed by - OBU; if no better task label is available, use Task - OBU.
5. Use the CLI for simple inspection or one-shot actions: info, tabs, user-tabs, history, open-tab, navigate, cdp, and call.
6. Use open-browser-use run / obu run for CLI-level multi-step orchestration when a small line-oriented action plan is enough and writing SDK code would be unnecessary.
7. If the surrounding agent runtime supports local MCP servers, configure obu mcp and call the exposed browser tools directly. Use the run_action_plan MCP tool for the same line-oriented orchestration from MCP. Read references/sdk-and-protocol.md.
8. Use the JavaScript, Python, or Go SDK for larger multi-step workflows, event subscriptions, richer control flow, or when the surrounding agent runtime already runs code. Read references/sdk-and-protocol.md.
9. Before ending browser work, release or keep session tabs with open-browser-use finalize-tabs --session-id "$OBU_SESSION_ID" --keep '\x3Cjson-array>', the MCP finalize_tabs tool, or the SDK finalizeTabs / finalize_tabs / FinalizeTabs method.
10. If communication fails after setup, read references/troubleshooting.md.

Operating Rules

• Treat the browser as the user's real Chrome profile. Do not inspect cookies, passwords, session stores, or unrelated browser data.
• Ask the user before installing the extension, opening Chrome for them, enabling extension permissions, uploading local files, reading/writing clipboard data, submitting forms, purchasing, deleting, sending, or making other externally visible changes.
• Do not assume Codex.app helpers, Node REPL globals, or a bundled plugin UI are available. Use the installed open-browser-use / obu CLI or the published SDKs.
• Do not guess tab ids. List tabs first, then use ids returned by tabs, user-tabs, open-tab, or SDK calls.
• Prefer claim-tab / claimUserTab for existing user tabs. Claiming should be based on the current user-tabs result and visible evidence such as URL, title, recency, or group.
• Use --socket only when the user or runtime provides an explicit socket. Otherwise let the CLI and SDKs discover the active socket registry.
• Do not rely on the CLI fallback session obu-cli for agent tasks. Always pass a task-unique --session-id to CLI and MCP commands, or set sessionId / session_id / SessionID in SDK clients. The fallback exists for quick manual use and can reuse stale task groups across unrelated agent sessions.
• Direct CLI subcommands and open-browser-use run can share the same browser session only when they use the same explicit --session-id. Finalize that same session before ending browser work.
• Use call --method \x3Cmethod> --params '\x3Cjson>' only when no safer convenience command or SDK wrapper exists.

Multi-profile handling

Some users run Chrome with several profiles (work, personal, side accounts). If more than one profile has the Open Browser Use extension installed, the agent must decide which profile this task should operate on rather than silently picking whatever Chrome window happens to be active.

1. Before any browser command, list installed profiles:

   open-browser-use profiles --connected
   

   Columns: DIRECTORY (stable id like Default, Profile 1), DISPLAY NAME (what the user sees in the Chrome avatar menu), VERSION, and CONNECTED (whether that profile's host is currently reachable). JSON output is available via --json.

2. If exactly one profile is installed and connected, proceed without asking. If it is installed but not connected, ask the user to open Chrome on that profile before running browser commands.

3. If multiple profiles are installed and the user did not already specify which one to use, ask before the first browser command. List both directory name and display name so the user can recognize them, and include whether each profile is connected.

4. If the chosen profile is not connected, ask the user to open Chrome on that profile before retrying. Do not silently fall back to a different connected profile.

5. After the user has chosen, pass --profile \x3Cselector> to every CLI / MCP command for the rest of the task. The selector accepts either the directory name (Default, Profile 1) or the display name (Eva, cookiy.com), case-insensitive. Do not switch profiles mid-task.

6. If --profile does not match any running host, the CLI prints which profiles are currently connected. Ask the user to open Chrome on the chosen profile, then retry; do not silently fall back to a different profile.

7. For MCP, lock the profile at server start:

   [mcp_servers.open_browser_use]
   command = "obu"
   args = ["mcp", "--session-id", "obu-\x3Ctask-id>", "--profile", "\x3Cselector>"]
   

   Do not pass profile as a per-tool-call argument — the MCP server applies the start-time selector to every call.

8. Do not remember the user's profile choice across unrelated tasks. A future task may belong to a different profile; ask again rather than assuming.

Common CLI Actions

export OBU_SESSION_ID="obu-docs-scan-$(date +%Y%m%d%H%M%S)"
open-browser-use ping --session-id "$OBU_SESSION_ID"
open-browser-use info --session-id "$OBU_SESSION_ID"
open-browser-use name-session --session-id "$OBU_SESSION_ID" --name "Task - OBU"
open-browser-use tabs --session-id "$OBU_SESSION_ID"
open-browser-use user-tabs --session-id "$OBU_SESSION_ID"
open-browser-use history --session-id "$OBU_SESSION_ID" --query "example" --limit 20
open-browser-use open-tab --session-id "$OBU_SESSION_ID" --url https://example.com
open-browser-use navigate --session-id "$OBU_SESSION_ID" --tab-id \x3Ctab-id> --url https://example.com
open-browser-use cdp --session-id "$OBU_SESSION_ID" --tab-id \x3Ctab-id> --method Runtime.evaluate --params '{"expression":"document.title"}'
open-browser-use finalize-tabs --session-id "$OBU_SESSION_ID" --keep '[]'

For CLI-level orchestration without writing SDK code, use a line-oriented action plan:

open-browser-use run --session-id "$OBU_SESSION_ID" -c '
name-session "Docs scan - OBU"
open-tab https://docs.browser-use.com
wait-load domcontentloaded
page-info
finalize-tabs []
'

Each action line shares one session/turn. open-tab and claim-tab set the default tab for later tab-scoped actions such as wait-load, page-info, navigate, cdp, move-mouse, and wait-file-chooser.

Use obu as the short alias when available.

MCP Usage

For runtimes that can launch local MCP servers over stdio, use:

[mcp_servers.open_browser_use]
command = "obu"
args = ["mcp", "--session-id", "obu-\x3Ctask-or-conversation-id>"]

Use a fresh --session-id value per agent task or conversation. If the runtime has a stable conversation/session id, derive the MCP --session-id from it.

The MCP server exposes tools including user_tabs, open_tab, claim_tab, navigate, wait_load, page_info, cdp, history, run_action_plan, finalize_tabs, and unrestricted call.

Use run_action_plan when the runtime wants to execute the same compact action plan format available through open-browser-use run without shelling out for each individual browser operation.

Tab Lifecycle

• Session tabs are tabs Open Browser Use has created or claimed for the current agent workflow.
• Use one unique session id per agent task or conversation. Do not share the fallback obu-cli session across unrelated tasks.
• Task session groups should be named from the task, using the pattern \x3Cshort task> - OBU. Use Task - OBU as the fallback name.
• Keep no tabs by default: open-browser-use finalize-tabs --session-id "$OBU_SESSION_ID" --keep '[]'.
• Keep a tab only when the user needs that live page after the turn. Omit research, source, search, intermediate, duplicate, blank, error, and login/navigation tabs after extracting what you need.
• Keep a tab with status: "deliverable" when the tab itself is the user-facing output or requested open page, such as a created or edited document, dashboard, checkout/cart, submitted form result, or a page the user explicitly asked to inspect directly.
• Keep a tab with status: "handoff" only when the task is still in progress and the user or a later turn should continue from the current task group, such as a page waiting for user input, login, approval, payment, CAPTCHA, or an unfinished workflow.
• Handoff tabs stay in the task session group. Deliverable tabs move to the shared ✅ Open Browser Use tab group.
• Run finalization as the last Open Browser Use browser action for the turn. Do not call Open Browser Use browser tools after finalizing; if more browser work is needed, do it first and finalize once with the final tab disposition.

File Choosers, Downloads, And Clipboard

• File uploads use the intercepted file chooser flow: start waiting, trigger the chooser in the page, then set absolute local paths with set-file-chooser-files or the SDK equivalent.
• Downloads can be observed with SDK notification handlers or Browser Use methods such as waitForDownload and downloadPath.
• Clipboard helpers operate through the current controlled tab and should be treated as sensitive user actions.

References

• references/installation.md: one-time CLI and browser extension setup, including cases where user cooperation is required.
• references/sdk-and-protocol.md: JavaScript, Python, Go, socket, and JSON-RPC usage details.
• references/troubleshooting.md: connection failures, stale sockets, extension/native host checks, and permission issues.