Files
hermes-agent/tools/browser_use_cli.py
ethernet 3f4b8840f1 Merge remote-tracking branch 'origin/main' into ethie/pm-clean
# Conflicts:
#	pyproject.toml
#	tests/fixtures/resolution_allowlist.json
2026-09-23 07:36:31 -04:00

784 lines
40 KiB
Python

"""Use the Browser Use CLI 3.0 (https://browser-use.com) for browser automation
When browser.backend is "browser-use", the model gets ``browser_exec`` tool
instead of default browser tools
"""
import contextlib
import importlib
import json
import logging
import os
import re
import signal
import subprocess
import time
from pathlib import Path
from typing import Any, Callable, Dict, List, Optional, Tuple
from hermes_constants import get_hermes_home
from utils import is_truthy_value
logger = logging.getLogger(__name__)
_BACKEND_KEY = "browser-use"
BACKEND_DISABLED = "off"
# Cloud daemon names become the BU_NAME env var
_SESSION_RE = re.compile(r"^[A-Za-z0-9][A-Za-z0-9_-]{0,63}$")
# Set on the env dict by the CDP resolvers when the resolved browser is EXCLUSIVE to this named session
# (per-name provider / named BU cloud / Lightpanda). Popped before the subprocess launches — never exported.
_PRIVATE_BROWSER_SENTINEL = "_HERMES_BU_PRIVATE_BROWSER"
# Internal route provenance: this exec resolved to a browser on the Bot Desktop display and must use
# the same human-control lease fence as the built-in browser tools. Popped before launching the CLI.
_BOT_DESKTOP_BROWSER_SENTINEL = "_HERMES_BU_BOT_DESKTOP_BROWSER"
# Prepended to the model's code for named sessions on SHARED browsers (a /browser connect CDP override): the
# harness daemon attaches to the first existing page at startup, so two fresh named daemons can land on the
# SAME tab. Steering each onto a tab it created prevents clobbering. Runs once per daemon (marker keyed by
# BU_NAME + daemon pid).
_OWN_TAB_PREAMBLE = """\
# hermes: pin this named session to its own tab (once per daemon process)
def _hermes_ensure_own_tab():
import os as _os, tempfile as _tf
_name = _os.environ.get("BU_NAME", "default")
try:
# Key the marker by the daemon's pid so a daemon restart (which
# re-attaches to the first shared page) re-pins automatically,
# while agent-driven tab switches mid-session are left alone.
from browser_harness import _ipc as _bipc
_dpid = _bipc.pid_path(_name).read_text().strip() or "0"
except Exception:
_dpid = "0"
_uid = _os.getuid() if hasattr(_os, "getuid") else 0
_marker = _os.path.join(
_tf.gettempdir(), "hermes-bu-owntab-%s-%s-%s" % (_uid, _name, _dpid)
)
if _os.path.exists(_marker):
return
try:
# Force a fresh target: new_tab() would REUSE a blank current tab,
# which is exactly the tab a sibling daemon may also hold.
_tid = cdp("Target.createTarget", url="about:blank").get("targetId")
if _tid:
switch_tab(_tid)
except Exception:
pass # best-effort: worst case is pre-fix behavior
try:
open(_marker, "w").close()
except OSError:
pass
_hermes_ensure_own_tab()
del _hermes_ensure_own_tab
"""
_DEFAULT_TIMEOUT_S = 300
_MIN_TIMEOUT_S = 5
_MAX_TIMEOUT_S = 1800
_STDERR_CAP_CHARS = 4000
_TASK_ID_SAFE_RE = re.compile(r"[^A-Za-z0-9._-]+") # filesystem-safe task ids
# Screenshot paths printed by capture_screenshot(): POSIX or Windows drive-letter absolute.
_IMAGE_PATH_RE = re.compile(r"((?:[A-Za-z]:[\\/]|/)[^\s\"']+?\.(?:png|jpe?g|webp))", re.IGNORECASE)
# http(s) URL literals in exec code checked against browser_navigate's policy
_URL_RE = re.compile(r"https?://[^\s'\"\\)]+", re.IGNORECASE)
_FHS_BIN_DIRS = ("/usr/local/sbin", "/usr/local/bin", "/usr/sbin", "/usr/bin", "/sbin", "/bin")
def _quiet(fn: Callable[[], Any], default: Any, log_prefix: str = "") -> Any:
"""``fn()``, or ``default`` on any exception (debug-logged when ``log_prefix`` is set)."""
try:
return fn()
except Exception as e:
if log_prefix:
logger.debug("%s: %s", log_prefix, e)
return default
def _lazy_call(module: str, name: str, default: Any, log_prefix: str) -> Any:
"""Call ``module.name()`` resolved at call time (tests stub the module / patch the
attribute); on any failure log ``log_prefix`` and return ``default``."""
return _quiet(lambda: getattr(importlib.import_module(module), name)(), default, log_prefix)
def _camofox_active(context: str = "") -> bool:
return _lazy_call("tools.browser_camofox", "is_camofox_mode", False, f"Camofox activity check failed{context}")
def _real_profile_consented() -> bool:
return _lazy_call("tools.browser_tool_cloud", "_use_real_profile", False, "real-profile consent lookup failed")
def _set_cdp_env(env: dict, cdp: str) -> None:
"""Export a CDP endpoint under the BU_CDP_* contract (http(s) → URL, else WS)."""
env["BU_CDP_URL" if cdp.startswith(("http://", "https://")) else "BU_CDP_WS"] = cdp
def _has_cdp_env(env: dict) -> bool:
return bool(env.get("BU_CDP_WS") or env.get("BU_CDP_URL"))
def _export_session_cdp(env: dict, get_session_info: Callable[[str], Any], cache_key: str,
fail_msg: Callable[[Exception], str], no_cdp_msg: str) -> Optional[str]:
"""Export the CDP endpoint from ``get_session_info(cache_key)``; error string on failure / no CDP."""
try:
cdp = str((get_session_info(cache_key) or {}).get("cdp_url") or "")
except Exception as e:
return fail_msg(e)
if not cdp:
return no_cdp_msg
_set_cdp_env(env, cdp)
return None
def _blocked_url_in_code(code: str) -> Optional[str]:
"""Return an error if a URL literal fails the built-in navigation checks."""
from tools.browser_tool import evaluate_url_safety
return next((err.get("error", "Blocked: unsafe URL") for err in map(evaluate_url_safety, _URL_RE.findall(code or "")) if err), None)
def _base_subprocess_env() -> dict:
from tools.browser_tool import _build_browser_env
env = _build_browser_env()
# The CLI runs under its own PM-managed Python; an inherited PYTHONPATH/PYTHONHOME
# (Hermes's venv) wins over its site-packages → wrong-ABI C-extensions and a crash.
# PYTHONPATH/PYTHONHOME inherited from the agent process point at Hermes's venv site-packages, and a
# child interpreter honors them ahead of its own site-packages — so the CLI imports compiled
# C-extensions (e.g. pydantic_core) built for the wrong interpreter and crashes on ABI mismatch (#83427,
# #84841, #86006, #86104). Strip both — the CLI manages its own environment and never needs Hermes's
# import path.
env.pop("PYTHONPATH", None)
env.pop("PYTHONHOME", None)
env["PATH"] = _floor_subprocess_path(env.get("PATH", ""))
env.setdefault("ANONYMIZED_TELEMETRY", "false")
return env
def _floor_subprocess_path(path: str) -> str:
"""Keep system commands reachable from profile workers with a minimal PATH.
Browser subprocesses may launch shell helpers; version-manager-only paths
omit /usr/bin. Reuse the shared browser PATH floor on POSIX.
"""
if os.name == "nt":
return path
with contextlib.suppress(Exception):
from tools.browser_tool_install import _merge_browser_path
return _merge_browser_path(path or "")
parts = [p for p in (path or "").split(os.pathsep) if p]
return os.pathsep.join(parts + [d for d in _FHS_BIN_DIRS if d not in set(parts) and os.path.isdir(d)])
def _read_browser_cfg() -> dict:
"""Return the ``browser:`` config section, or {} on any failure."""
try:
from hermes_cli.config import cfg_get, read_raw_config
cfg = cfg_get(read_raw_config(), "browser", default={})
return cfg if isinstance(cfg, dict) else {}
except Exception as e:
logger.debug("Could not read browser config section: %s", e)
return {}
def _use_gateway(browser_cfg: dict) -> bool:
"""True when the browser section selects the Nous Tool Gateway — by the current ``hermes tools``
picker row (``cloud_provider: nous``) or the pre-picker ``use_gateway: true`` flag. Reading only
the legacy flag missed every picker-configured gateway, and the direct-API branch it fell into
holds no credentials in managed mode (#108310)."""
if is_truthy_value(browser_cfg.get("use_gateway"), default=False):
return True
try:
from tools.tool_backend_helpers import NOUS_MANAGED_PROVIDER
except Exception: # pragma: no cover — helper ships with the package
return False
return str(browser_cfg.get("cloud_provider") or "").strip().lower() == NOUS_MANAGED_PROVIDER
def get_browser_backend() -> str:
"""Configured browser backend key ("" = unset → default). YAML 1.1 parses an
unquoted ``off`` as False — that must mean BACKEND_DISABLED, not "unset"."""
raw = _read_browser_cfg().get("backend")
return (BACKEND_DISABLED if raw is False else "") if isinstance(raw, bool) else str(raw or "").strip().lower()
def is_legacy_browser_use_cloud_config(browser_cfg: dict) -> bool:
"""True for pre-CLI direct-API Browser Use cloud configs. An explicit backend or
a non-Browser-Use cloud_provider wins; Camofox is selected via env var, not
cloud_provider, so a Camofox user with a stray BROWSER_USE_API_KEY keeps it."""
if not isinstance(browser_cfg, dict) or browser_cfg.get("backend"):
return False
provider = str(browser_cfg.get("cloud_provider") or "").strip().lower()
if provider not in {"browser-use", ""} or _use_gateway(browser_cfg) or _camofox_active(" during migration"):
return False
# Profile credential: a multiplexed secondary must not inherit the default's cloud mode.
from agent.secret_scope import get_secret
return bool(get_secret("BROWSER_USE_API_KEY", ""))
def is_browser_use_cli_mode() -> bool:
"""True when the Browser Use CLI replaces the built-in browser stack. Browser Use mode is the DEFAULT:
unset ``browser.backend`` ("") enables it whenever the PM-managed CLI is installed;
``browser.backend: off`` keeps the built-in browser_* tools. Camofox always falls back to the built-in
tools (Firefox, custom HTTP API, no CDP surface for the harness)."""
if _camofox_active():
return False
backend = get_browser_backend()
return backend == _BACKEND_KEY if backend else (is_legacy_browser_use_cloud_config(_read_browser_cfg()) or _find_cli() is not None)
def default_downgrade_notice() -> Optional[str]:
"""One-line notice when ``browser.backend`` is unset but the CLI is not runnable, so
the session fell back to the built-in tools. Rate-limited to once per 24h via a stamp file."""
try:
if get_browser_backend() or _camofox_active() or _find_cli() is not None:
return None # explicit choice / Camofox / CLI present — nothing downgraded
stamp = Path(get_hermes_home()) / "cache" / ".browser_use_default_notice"
now = time.time()
with contextlib.suppress(OSError):
if 0 <= now - stamp.stat().st_mtime < 24 * 3600:
return None
with contextlib.suppress(OSError):
stamp.parent.mkdir(parents=True, exist_ok=True)
stamp.touch()
os.utime(stamp, (now, now))
return ("Browser Use CLI not found — using the built-in browser tools. Run `hermes tools` "
"(Browser Automation → Browser Use) to install it, or `browser.backend: off` in config.yaml to silence this.")
except Exception as e: # pragma: no cover — a notice must never break startup
logger.debug("browser-use downgrade notice failed: %s", e)
return None
_CLI_REQUIREMENTS = ("browser-use==0.13.10",)
def _find_cli() -> Optional[List[str]]:
"""Read PM's selected CLI without installing anything during discovery."""
import pm
binary = pm.python_tool("browser-use", "browser-use")
return [str(binary)] if binary is not None else None
def install_cli(timeout_s: int = 600) -> Tuple[bool, str]:
"""Provision the pinned CLI in PM's isolated environment; never raises."""
try:
import pm
binary = pm.ensure_python_tool(
"browser-use", _CLI_REQUIREMENTS, "browser-use", explicit=True, timeout=timeout_s,
)
except Exception as exc:
return False, f"Could not install browser-use CLI: {exc}"
return True, f"browser-use CLI installed ({binary})"
def _workspace_dir(task_id: Optional[str]) -> Optional[str]:
"""Stable per-task scratch dir that persists across browser_exec calls"""
if os.environ.get("BH_AGENT_WORKSPACE"):
return os.environ["BH_AGENT_WORKSPACE"]
try:
safe = _TASK_ID_SAFE_RE.sub("_", str(task_id or "default"))[:80] or "default"
path = Path(get_hermes_home()) / "cache" / "browser-use" / "workspace" / safe
path.mkdir(parents=True, exist_ok=True)
return str(path)
except Exception as e:
logger.debug("browser_exec workspace unavailable: %s", e)
return None
def _find_screenshot(stdout: str, since: float) -> Optional[str]:
"""Last screenshot path printed during this exec that exists and was written after
the exec started, or None."""
for path in reversed(_IMAGE_PATH_RE.findall(stdout or "")):
try:
if os.path.isfile(path) and os.path.getmtime(path) >= since - 1:
return path
except OSError:
continue
return None
def _native_screenshot_result(result: Dict[str, Any], path: str) -> Optional[Dict[str, Any]]:
"""Build a multimodal tool result attaching path for vision models"""
try:
from tools.vision_tools import (_EMBED_MAX_DIMENSION,
_resize_image_for_vision, _should_use_native_vision_fast_path)
from tools.vision_tools_history_budget import resolve_embed_target_bytes
if not _should_use_native_vision_fast_path():
return None
# History-reuse cap: this data URL bakes into the tool result and is re-sent every later turn —
# same policy as the vision_analyze / browser_vision native embeds.
data_url = _resize_image_for_vision(Path(path), mime_type="image/png",
max_base64_bytes=resolve_embed_target_bytes(),
max_dimension=_EMBED_MAX_DIMENSION, force_jpeg=True)
text = json.dumps(result, ensure_ascii=False)
attached = text + "\n\nThe screenshot from this call is attached — inspect it with your native vision."
return {"_multimodal": True, "text_summary": text, "meta": {"screenshot_path": path, "native_vision": True},
"content": [{"type": "text", "text": attached}, {"type": "image_url", "image_url": {"url": data_url}}]}
except Exception as e:
logger.debug("Native screenshot attach failed (falling back to text): %s", e)
return None
def _served_profile_tag() -> str:
"""``""`` outside a served-profile scope (every legacy key stays byte-identical); under a
multiplexed turn, the routed profile's home key — one profile's browser must never be handed
to another that happens to use the same session name or task id (#110032)."""
from hermes_constants import get_hermes_home_override, hermes_home_key
return "" if get_hermes_home_override() is None else hermes_home_key()
def _backend_cache_key(task_id: Optional[str], session_name: str = "") -> str:
"""Session-cache key for a backend browser: named sessions get their own; served profiles get their own."""
key = f"bu-named-{session_name}" if session_name else (task_id or "browser-exec-default")
tag = _served_profile_tag()
return f"{key}@{tag}" if tag else key
def _resolve_lightpanda_cdp(env: dict, task_id: Optional[str], session_name: str = "") -> Optional[str]:
"""Point the harness at a Hermes-spawned ``lightpanda serve`` (``browser.engine: lightpanda`` and
nothing of higher precedence claimed the session). Each cache key gets its own process via the
legacy ``_get_session_info()`` (cache, reaper, atexit): private browser, own-tab preamble skipped."""
try:
from tools.browser_tool_session import _get_session_info
from tools.browser_tool_lightpanda_fallback import _using_lightpanda_engine
if not _using_lightpanda_engine():
return None
except Exception as e: # stubbed browser_tool in tests / engine lookup failure
logger.debug("browser engine lookup failed: %s", e)
return None
err = _export_session_cdp(
env, _get_session_info, _backend_cache_key(task_id, session_name),
lambda e: (f"Lightpanda could not be started: {e} Set browser.engine to auto "
"to use local Chrome, or switch backends via `hermes tools` → Browser Automation."),
"Lightpanda session returned no CDP endpoint. Set browser.engine to auto to use local Chrome.",
)
if err is None:
env[_PRIVATE_BROWSER_SENTINEL] = "1"
env[_BOT_DESKTOP_BROWSER_SENTINEL] = "1"
return err
def _resolve_managed_chromium_cdp(env: dict, task_id: Optional[str], session_name: str = "") -> Optional[str]:
"""Point the harness at Hermes' packaged Chromium, launched through agent-browser for this cache key —
the same browser the built-in tools drive. Left alone, the harness discovers the user's INSTALLED
Chrome on its default profile, which needs the chrome://inspect toggle + an Allow popup per run and
is blocked outright on Chrome >=136; on a headless box it just reports ``chrome-not-running``.
``get cdp-url`` runs through ``_run_browser_command`` (legacy cache, inactivity reaper, atexit, Chromium
preflight/auto-install) on EVERY call: it launches the browser cold, follows a relaunch, and refreshes
the agent-browser daemon's idle timer, which never sees the harness's direct CDP traffic."""
try:
from tools.browser_tool_session import _run_browser_command
from tools.browser_tool import _get_open_command_timeout
except Exception as e: # pragma: no cover — stubbed browser_tool in tests
logger.debug("managed chromium resolution unavailable: %s", e)
return None
res = _run_browser_command(_backend_cache_key(task_id, session_name), "get", ["cdp-url"],
timeout=_get_open_command_timeout(first_open=True))
cdp = str(((res or {}).get("data") or {}).get("cdpUrl") or "") if (res or {}).get("success") else ""
if not cdp:
return (f"The local browser could not be started: {(res or {}).get('error') or 'agent-browser returned no CDP endpoint'} "
"Run `hermes tools` → Browser Automation to (re)install Chromium, or switch backends.")
_set_cdp_env(env, cdp)
env[_PRIVATE_BROWSER_SENTINEL] = "1" # one Chromium per cache key: nothing to share a tab with
env[_BOT_DESKTOP_BROWSER_SENTINEL] = "1"
return None
def _resolve_local_engine_cdp(env: dict, task_id: Optional[str], session_name: str = "") -> Optional[str]:
"""Local engine (no provider / override): ``browser.engine: lightpanda`` or the packaged Chromium."""
err = _resolve_lightpanda_cdp(env, task_id, session_name)
if err or _has_cdp_env(env):
return err
return _resolve_managed_chromium_cdp(env, task_id, session_name)
def _resolve_backend_cdp(env: dict, task_id: Optional[str], session_name: str = "") -> Optional[str]:
"""Point the harness at the configured backend's CDP endpoint; error string on failure.
Precedence: (1) ``BU_CDP_WS``/``BU_CDP_URL`` already in env (operator override); (2) ``BROWSER_CDP_URL``
env / ``browser.cdp_url`` (``/browser connect``); (3) a cloud provider via the legacy ``_get_session_info()``
so browser_exec shares the SAME session machinery (per-task cache, expiry, reaper, atexit);
(4) the local engine — ``browser.engine: lightpanda`` or Hermes' packaged Chromium via agent-browser
(never the harness's own discovery of the user's installed Chrome); (5) BU direct-API configs → None:
the CLI reaches BU cloud natively (BU_AUTOSPAWN). ``session_name`` (BU_NAME) keys the session cache so
each name gets its OWN browser — what makes named sessions concurrent-safe.
"""
if _has_cdp_env(env):
return None
try:
from tools.browser_tool_cloud import _get_cloud_provider
from tools.browser_tool_session import _get_session_info
from tools.browser_tool_cdp import _get_cdp_override
except Exception as e: # pragma: no cover — stubbed browser_tool in tests
logger.debug("browser_tool backend resolution unavailable: %s", e)
return None
override = _quiet(_get_cdp_override, "")
if override:
_set_cdp_env(env, override)
return None
provider = _quiet(_get_cloud_provider, None, "Cloud provider lookup failed")
if provider is None:
return _resolve_local_engine_cdp(env, task_id, session_name)
# Browser Use direct-API configs: the CLI talks to BU cloud natively (BU_AUTOSPAWN / auth login) — the
# legacy provider would create a second, redundant session. Nous-gateway configs (cloud_provider: nous
# from the picker, or the pre-picker use_gateway: true) DO resolve through the provider: the gateway
# provisions the browser server-side and returns its CDP URL.
provider_key = str(getattr(provider, "name", "") or "").strip().lower()
if provider_key == _BACKEND_KEY and not _use_gateway(_read_browser_cfg()):
env[_PRIVATE_BROWSER_SENTINEL] = "1" # named BU cloud browsers are exclusive to their daemon
return None
provider_name = type(provider).__name__
err = _export_session_cdp(
env, _get_session_info, _backend_cache_key(task_id, session_name),
lambda e: (f"Cloud browser provider {provider_name} failed to provide a session: {e}. "
"Fix the provider configuration or switch backends via `hermes tools` → Browser Automation."),
f"Cloud browser provider {provider_name} returned no CDP endpoint, so Browser Use mode "
"cannot drive it. Switch to the built-in browser tools for this provider.",
)
# A provider browser keyed bu-named-<name> is exclusive to this session — the
# own-tab preamble would just leak a blank tab into it.
if err is None and session_name:
env[_PRIVATE_BROWSER_SENTINEL] = "1"
return err
def _resolve_real_profile_cdp(env: dict, force_local: bool) -> Optional[str]:
"""Point the harness at the user's real-profile copy-browser (a SNAPSHOT of their default Chromium
profile, hermes_cli.browser_connect) when consented. Two ways in: the effective backend is already local
(no provider, CDP override, or legacy BU cloud config) → silent upgrade; or ``force_local`` (consent-gated
``local`` arg) → the user's browser even under a cloud backend. Operator overrides (BU_CDP_* env,
/browser connect, ``browser.cdp_url``) own the session either way. Fail closed: a launch error is
returned so a consented user is never silently downgraded."""
if not _real_profile_consented() or _has_cdp_env(env):
return None
try:
from tools.browser_tool_cdp import _get_cdp_override_raw
from tools.browser_tool_cloud import _get_cloud_provider
from tools.browser_tool_real_profile import _real_profile_cdp
except Exception as e: # pragma: no cover — stubbed browser_tool in tests
logger.debug("real-profile backend resolution unavailable: %s", e)
return None
if _quiet(_get_cdp_override_raw, ""):
return None
# Only auto-upgrade genuinely-local attaches; any cloud path (provider, provider lookup failure, or
# legacy BU cloud config) stays on its backend unless the model passes local=true.
if not force_local and (_quiet(_get_cloud_provider, object()) is not None
or is_legacy_browser_use_cloud_config(_read_browser_cfg())):
return None
cdp, err = _real_profile_cdp()
if cdp and not err:
_set_cdp_env(env, cdp)
env[_BOT_DESKTOP_BROWSER_SENTINEL] = "1"
return err or None
def _attach_vault_supervisor(env: dict, task_id: Optional[str]) -> None:
"""Attach the per-task CDP supervisor to the browser this exec drives so ``browser_vault_fill`` has
a secret-capable WebSocket (never argv) into the SAME browser. Only CDP-routed backends expose an
endpoint; BU direct-cloud (BU_AUTOSPAWN) does not, and the vault tools report ``supervisor_required``."""
cdp = env.get("BU_CDP_WS") or env.get("BU_CDP_URL")
if not cdp:
return
try:
from tools.browser_supervisor import SUPERVISOR_REGISTRY
from tools.browser_tool_cdp import _get_dialog_policy_config, _resolve_cdp_override
policy, timeout_s = _get_dialog_policy_config()
SUPERVISOR_REGISTRY.get_or_start(task_id=task_id or "default", cdp_url=_resolve_cdp_override(cdp),
dialog_policy=policy, dialog_timeout_s=timeout_s)
except Exception as exc:
logger.debug("browser_exec: CDP supervisor attach failed (non-fatal): %s", exc)
def _route_backend(env: dict, session: str, task_id: Optional[str], local: bool) -> Optional[str]:
"""Resolve where the harness connects; returns an error string or None. Real-profile consent runs
BEFORE provider resolution so a hit short-circuits the cloud path via the BU_CDP_* env contract. Named
sessions compose with the backend: BU_NAME namespaces the harness daemon (IPC socket, log, pid) and on
provider backends additionally keys its own cloud browser."""
rp_err = _resolve_real_profile_cdp(env, force_local=local)
if rp_err:
return rp_err
# local=True is only served by the real-profile route; consent off must not pretend.
if local and not _has_cdp_env(env) and not _real_profile_consented():
return ("local=true was requested but browser.use_real_profile is off. Enable it in config.yaml "
"(browser.use_real_profile: true) or the desktop Settings → Browser section, then retry.")
return _resolve_backend_cdp(env, task_id, session_name=session)
def _group_popen_kwargs() -> dict:
"""Popen kwargs starting the CLI in its own process group (a new session on POSIX) so a
timeout can take down every process that inherited the capture pipes, not just the CLI
child. Windows also hides the console the .cmd shim would flash (as browser_tool does)."""
def _flags() -> dict:
from hermes_cli._subprocess_compat import windows_hide_flags
si = subprocess.STARTUPINFO()
si.dwFlags |= subprocess.STARTF_USESHOWWINDOW
return {"creationflags": windows_hide_flags() | getattr(subprocess, "CREATE_NEW_PROCESS_GROUP", 0),
"startupinfo": si}
return _quiet(_flags, {}, "Windows hide-flags unavailable") if os.name == "nt" else {"start_new_session": True}
def _clamp_timeout(timeout_s: Any) -> int:
try:
return max(_MIN_TIMEOUT_S, min(int(timeout_s), _MAX_TIMEOUT_S))
except (TypeError, ValueError):
return _DEFAULT_TIMEOUT_S
# After a whole-group SIGKILL, every pipe holder is dead, so the drain below is normally
# instant; the deadline only guards against a process outside the group still holding a pipe.
_POST_KILL_DRAIN_S = 10.0
def _kill_cli_process_group(proc) -> None:
"""SIGKILL the CLI's whole process group (POSIX; ``start_new_session`` made pgid == pid) or,
on Windows, its process tree via ``taskkill /T /F`` — the only group-wide kill it offers."""
if os.name == "nt":
from hermes_cli._subprocess_compat import windows_hide_flags
with contextlib.suppress(OSError, subprocess.SubprocessError):
subprocess.run(["taskkill", "/T", "/F", "/PID", str(proc.pid)], stdin=subprocess.DEVNULL,
capture_output=True, text=True, encoding="utf-8", errors="replace", timeout=10,
check=False, creationflags=windows_hide_flags())
return
with contextlib.suppress(ProcessLookupError, PermissionError):
os.killpg(proc.pid, signal.SIGKILL) # windows-footgun: ok — POSIX only, the nt branch returned above
def _run_cli_killing_process_group(cmd, code, env, timeout):
"""Run the CLI in its own process group and kill the whole group on timeout.
``subprocess.run`` only kills the direct child on ``TimeoutExpired``; a grandchild that
inherited the stdout/stderr pipes (browser_harness daemon / Chrome helper) is orphaned
still holding them, and on Windows ``run()``'s unbounded post-kill ``communicate()`` then
blocks on pipe EOF forever — so the tool call, plus its activity heartbeat, wedges (#106244).
"""
proc = subprocess.Popen(
cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE,
text=True, encoding="utf-8", errors="replace", env=env, **_group_popen_kwargs(),
)
try:
stdout, stderr = proc.communicate(input=code, timeout=timeout)
except subprocess.TimeoutExpired:
_kill_cli_process_group(proc)
with contextlib.suppress(subprocess.TimeoutExpired):
proc.communicate(timeout=_POST_KILL_DRAIN_S)
raise
return subprocess.CompletedProcess(cmd, proc.returncode, stdout, stderr)
def browser_exec(code: str, session: str = "", timeout_s: int = _DEFAULT_TIMEOUT_S,
task_id: Optional[str] = None, local: bool = False):
"""Run Python code through the browser-use CLI, and return its output"""
from agent.redact import redact_sensitive_text
from tools.registry import tool_error, tool_result
if not code or not code.strip():
return tool_error("No code provided. Pass Python that uses the pre-imported helpers, e.g. new_tab(\"https://example.com\") then print(page_info()).")
blocked = _blocked_url_in_code(code)
if blocked:
return tool_error(blocked)
cmd = _find_cli()
if not cmd:
return tool_error("The PM-managed browser-use CLI is not installed. "
"Run `hermes tools` (Browser Automation → Browser Use) to install it.")
env = _base_subprocess_env()
if session:
if not _SESSION_RE.match(session):
return tool_error(f"Invalid session name {session!r}: use 1-64 letters, digits, "
"dashes, or underscores (e.g. 'r7k2').")
env["BU_NAME"] = session
route_err = _route_backend(env, session, task_id, bool(local))
if route_err:
return tool_error(route_err)
bot_desktop_browser = bool(env.pop(_BOT_DESKTOP_BROWSER_SENTINEL, None))
# SHARED browser (/browser connect CDP override): pin each named session to its own tab (see
# _OWN_TAB_PREAMBLE). Private per-name browsers skip this — nothing to collide with.
private_browser = env.pop(_PRIVATE_BROWSER_SENTINEL, None) # always pop: never exported to the CLI
if session and not private_browser:
code = _OWN_TAB_PREAMBLE + code
workspace = _workspace_dir(task_id)
if workspace:
env["BH_AGENT_WORKSPACE"] = workspace
# BU_AUTOSPAWN makes the CLI start a Browser Use cloud browser when no local
# Chrome/CDP endpoint is reachable (their API key authenticates it)
if "BU_AUTOSPAWN" not in env and is_legacy_browser_use_cloud_config(_read_browser_cfg()):
env["BU_AUTOSPAWN"] = "1"
timeout = _clamp_timeout(timeout_s)
started = time.time()
def dispatch() -> Dict[str, Any]:
_attach_vault_supervisor(env, task_id)
try:
return {"proc": _run_cli_killing_process_group(cmd, code, env, timeout)}
except subprocess.TimeoutExpired:
return {"error_result": tool_error(
f"browser-use exec timed out after {timeout}s. The daemon may still be working; retry "
f"with a larger timeout_s (max {_MAX_TIMEOUT_S}), or split the work into several calls that "
"append to workspace files — anything already written to the workspace is preserved."
)}
except OSError as e:
return {"error_result": tool_error(f"Failed to launch browser-use CLI: {e}")}
if bot_desktop_browser:
from tools.browser_tool_session import run_fenced
dispatched = run_fenced({"features": {"local": True}}, dispatch)
else:
dispatched = dispatch()
if "proc" not in dispatched:
if "error_result" in dispatched:
return dispatched["error_result"]
return tool_result(dispatched)
proc = dispatched["proc"]
# browser_vault_fill registers injected values with this forced model-egress
# boundary. Preserve raw stdout only for screenshot-path detection below.
result = {
"success": proc.returncode == 0,
"exit_code": proc.returncode,
"output": redact_sensitive_text(proc.stdout, force=True),
}
if workspace:
result["workspace"] = workspace
if session:
result["session"] = session
stderr = redact_sensitive_text((proc.stderr or "").strip(), force=True)
if len(stderr) > _STDERR_CAP_CHARS:
stderr = stderr[:_STDERR_CAP_CHARS] + "\n… (stderr truncated)"
if stderr:
result["stderr"] = stderr
screenshot = _find_screenshot(proc.stdout, started)
if screenshot:
result["screenshot_path"] = screenshot
native = _native_screenshot_result(result, screenshot)
if native is not None:
return native
return tool_result(result)
_HEADER_BASE = (
"Drive a real web browser via the Browser Use CLI: `code` runs as full Python (stdlib available) "
"with pre-imported browser helpers; stdout comes back in the result. Start `code` with a one-line "
"comment describing the step for the user in plain language, max 60 chars "
"(e.g. `# Searching Amazon for paper towels`) — the UI shows it as the step label.\n\n"
"STATE: the browser session and workspace persist across calls; Python variables do NOT (fresh "
"interpreter each call). The workspace dir is $BH_AGENT_WORKSPACE (also `workspace` in every result); "
"functions defined in agent_helpers.py there are auto-imported into every call. For multi-item tasks "
"('all N products / every entry'), append each batch to a JSON/CSV file in the workspace, then read it "
"back and aggregate in code — dedupe/count/sort with Python, not in your head — and verify the "
"collected count against what was asked before answering.\n\n"
"Batch each sub-procedure (navigate, wait, extract, act) into one call — do not spend a call per "
"action — but for long extractions prefer several medium calls that append to workspace files over "
"one giant call, so progress survives timeouts."
)
_HEADER_VISION = (
" Screenshots are attached to your context automatically: when the exec output contains a "
"capture_screenshot() path, the image arrives with this tool's result and you inspect it directly "
"with your own vision — never send browser screenshots to a separate vision tool."
)
_HEADER_TEXT_ONLY = (
" Your model cannot view images, so work text-first: page_info() for state, js() for "
"reading/extracting DOM text, fill_input(selector, text) for inputs, and "
"js(\"document.querySelector('…').click()\") for clicks — skip the screenshot-driven workflow described below."
)
# Appended when the local engine is Lightpanda: no graphical renderer, and one CDP
# connection holds one page — a second Target.createTarget fails with
# TargetAlreadyLoaded (drop the new_tab() sentence once lightpanda-io/browser#1962 lands).
_HEADER_LIGHTPANDA = (
" The local engine is Lightpanda (no graphical renderer, one page per session): capture_screenshot() "
"is unavailable, so work text-first; navigate with new_tab(url) exactly once, then goto_url(url) for "
"every later navigation — a second new_tab() fails with TargetAlreadyLoaded."
)
# Pinned quick-reference for the CLI's pre-imported helpers, replacing the live
# ``browser-use skill`` fetch (uncontrolled third-party text in every schema: version
# drift, supply-chain exposure, byte-unstable prompt). A/B benchmarked ~equal.
_HELPERS_DIGEST = (
"\n\nHELPERS (pre-imported): new_tab(url) opens/navigates (use for the FIRST navigation), goto_url(url) "
"navigates the current tab, wait_for_load() after navigation, page_info() summarizes the current page "
"state, js(expr) evaluates a JS expression and returns its value (js('document.title'); wrap function "
"bodies as js('(() => {...})()') — a bare '() => {...}' returns the function itself, uncalled), "
"fill_input(selector, text) types into inputs, click_at_xy(x, y) clicks viewport coordinates, "
"capture_screenshot() saves and prints a screenshot path, cdp('Domain.method', **kwargs) is raw CDP — "
"cdp('Accessibility.getFullAXTree')['nodes'] lists every element's role/name/backendDOMNodeId (filter "
"in Python before printing; it is thousands of nodes), then cdp('DOM.getBoxModel', backendNodeId=n) "
"gives click coordinates. ensure_real_tab() recovers from a stale/internal tab. Login walls: never guess "
"credentials; see the vault note below if present, otherwise stop and ask the user."
)
def _description_header() -> str:
"""Header tailored to whether the active model can see images natively"""
if _lazy_call("tools.browser_tool_lightpanda_fallback", "lightpanda_engine_status", (False, ""),
"lightpanda engine status unavailable")[0]: # no screenshots, whatever the model sees
return _HEADER_BASE + _HEADER_TEXT_ONLY + _HEADER_LIGHTPANDA
vision = _lazy_call("tools.vision_tools", "_should_use_native_vision_fast_path", False, "")
return _HEADER_BASE + (_HEADER_VISION if vision else _HEADER_TEXT_ONLY)
def _dynamic_schema_overrides() -> dict:
overrides: dict = {"description": _description_header() + _HELPERS_DIGEST}
# ``local`` exists ONLY when the user consented to real-profile browsing — everyone
# else's schema carries zero extra surface. The caller memoizes on config.yaml mtime,
# so toggling consent applies next session, not mid-chat.
if _real_profile_consented():
props = dict(BROWSER_EXEC_SCHEMA["parameters"]["properties"])
props["local"] = {
"type": "boolean", "default": False,
"description": ("Drive the user's own local browser (a Hermes-managed copy of their real "
"default-Chromium profile, logins/cookies included) instead of the configured "
"cloud browser backend. Use when the user asks to act as themselves — their "
"accounts, their sessions. No-op when the backend is already local. Default false."),
}
overrides["parameters"] = {**BROWSER_EXEC_SCHEMA["parameters"], "properties": props}
return overrides
BROWSER_EXEC_SCHEMA = {
"name": "browser_exec",
# Static fallback description, used only when the managed CLI is unavailable
"description": (_HEADER_BASE + _HELPERS_DIGEST
+ "\n\n(The browser-use CLI is not installed yet. Install it with `hermes tools` (Browser Automation → Browser Use).)"),
"parameters": {
"type": "object",
"properties": {
"code": {"type": "string", "description": "Python code to execute using the pre-imported browser helpers. Use print(...) for any data you need back."},
"session": {"type": "string", "description": "Named isolated browser session — its own daemon and (on cloud backends) own browser, so concurrent tasks don't share tabs. Reuse the same name on every related call; omit for the shared default session."},
"timeout_s": {"type": "integer", "default": _DEFAULT_TIMEOUT_S,
"description": f"Max seconds to wait for the code to finish (default {_DEFAULT_TIMEOUT_S}, max {_MAX_TIMEOUT_S})."},
},
"required": ["code"],
},
}
# browser_exec is additionally gated at tool-definition time — sessions whose toolsets
# lack ``terminal`` never see it (model_tools._compute_tool_definitions). check_fn only
# answers "is Browser Use mode configured"; surface policy lives with the session.
from tools.registry import registry
registry.register(
name="browser_exec",
toolset="browser-use",
schema=BROWSER_EXEC_SCHEMA,
handler=lambda args, **kw: browser_exec(
code=args.get("code", ""), session=args.get("session", "") or "",
timeout_s=args.get("timeout_s", _DEFAULT_TIMEOUT_S), task_id=kw.get("task_id"),
local=bool(args.get("local", False)),
),
check_fn=is_browser_use_cli_mode,
dynamic_schema_overrides=_dynamic_schema_overrides,
emoji="🌐",
)