pi-chrome browser-control benchmark
Static benchmark pages for evaluating tools that let agents control Chrome. The suite has two layers:
- Unit challenges (
manifest.json) — MiniWoB-style capability probes for forms, scroll containers, contenteditable, files, frames, Shadow DOM, network/console inspection,isTrusted, user activation, pointer paths, key cadence, native controls, drag/drop, touch, paste, and scroll momentum. - Long-horizon hermetic tasks (
task-manifest.json) — WebArena / BrowserGym-inspired multi-step tasks with fresh run IDs and deterministic programmatic graders.
Run
cd test-suite
python3 -m http.server 8765
# open http://127.0.0.1:8765/ in the Chrome window pi-chrome controls
Each challenge page exposes:
window.__challenge— idwindow.__verdict—"PENDING" | "PASS" | "FAIL" | "SKIP" | "WARN"window.__reason— array of reasonswindow.__events— raw event log for forensics
manifest.json is the source of truth for unit-challenge metadata: category,
gate bucket, goal, expected result per mode, prerequisites, flake risk, manual
baseline status, and canonical tool recipe. manifest.schema.json documents the
manifest shape. Recipes express tool intent; runners may need to adapt
descriptive selectors (e.g. shadow/iframe notation), dynamic tab ids, and expand
path placeholders like $PWD.
task-manifest.json is the source of truth for long-horizon tasks: BrowserGym-style
taskId, seed, viewport, goal object, difficulty tier, max steps, declared
action subsets, reset/setup URL, validate hook, optional cheat recipe, and
programmatic grader expression. task-manifest.schema.json documents this shape.
browsergym-action-space.json records BrowserGym-compatible action subsets.
Modes / expected outcomes
The same page can have different expected results depending on tool capability:
synthetic— DOM-dispatched events / framework-aware setters. Fast and quiet.trusted— browser-trusted input, usually viachrome.debugger/CDP. Can show Chrome's debugging banner.manual— human baseline in same browser/profile.
Expected values in manifest.json:
PASS/FAIL— deterministic target for that mode.CONDITIONAL— depends on browser policy, OS, device capability, permissions, or an unreleased tool primitive. Inspectprerequisites,notes, andflakeRisk.
Manual baselines are tracked separately with manualBaseline. unverified
means the manual expectation is a target, not a recorded contract.
Gate buckets
Each unit challenge has a gate field:
core— required release blocker for normal trusted-mode pi-chrome shipping.conditional— blocks only when declared prerequisites/capabilities are present (clipboard, touch, dialogs, native UI, etc.).quality— adversarial humanization/fingerprint signal. Track regressions, but do not block general ship without an explicit product decision.
Recommended unit-challenge agent flow
- Navigate to dashboard:
http://127.0.0.1:8765/. - Pick mode (
synthetic,trusted, ormanual) and clear local verdicts. - For each manifest row:
chrome_navigatetohttp://127.0.0.1:8765/<file>.chrome_snapshotbefore acting; prefer snapshotuidover raw selector.- Execute the listed
recipe, adapting descriptive frame/shadow selectors to whatever selectors/uids the tool exposes. - Read:
JSON.stringify({ v: window.__verdict, r: window.__reason, e: window.__events?.slice(-20) })
- Return to dashboard and compare actual verdicts with expected values.
- Copy JSON report from dashboard for PRs or regression notes.
Recommended long-horizon task flow
- Load
task-manifest.json. - Replace
$RUN_IDinstartUrlwith a fresh value. - Navigate to the start URL and read the visible task instruction.
- Solve using normal browser tools only; avoid direct state mutation unless the benchmark mode explicitly allows evaluate-based actions.
- Click Grade now or evaluate the task grader expression:
JSON.stringify({ v: window.__taskVerdict, r: window.__taskReason }) - Record action count, observations used, tools used, verdict, and reason.
Design principles copied from browser-agent benchmarks
- Prefer hermetic sites and deterministic graders over live sites and LLM judges.
- Report action API and observation format; these strongly affect scores.
- Use difficulty tiers: L1 atomic, L2 compositional, L3 cross-page/context-rich.
- Include tedious cross-page memory and exact-value transfer tasks; short unit probes hide these failures.
- Keep synthetic-event-gated tests because extension bridges face failures that CDP/Playwright-style benchmarks usually do not measure.
Challenge categories
trusted-input— browser-trusted click/key events.pointer-humanization— paths, coordinates, movement continuity/rate.keyboard/focus-keyboard— typing fidelity, modifiers, Tab flows.activation-gates— clipboard/fullscreen/user activation.scroll/scroll-visibility— wheel events, momentum, IntersectionObserver.drag-drop— HTML5 drag/drop +DataTransfer.clipboard— OS/browser paste path.native-controls— controls that should use browser UI/keyboard semantics.frameworks/editing— React-style value tracking, contenteditable.dom-complexity/frames— Shadow DOM and iframe targeting.files— file attachment to<input type=file>.observability— console/network capture tools.csp— strict Content Security Policy: screenshot/coordinate fallback (39) and the CDP eval/snapshot bypass that works underscript-src 'self'withoutunsafe-eval(42).lazy-loading— dynamic DOM readiness and wait behavior.fingerprint— environment and stack fingerprint probes.agent-safety— hidden honeypots and safe target selection.
Current challenge inventory
The dashboard renders this from manifest.json. In brief:
- trusted click
- trusted keyboard
- webdriver/runtime flags
- mouse entropy before click
- click timing
- click coordinate variation
- pointer event properties
- keyboard cadence
- beforeinput/input order
- user activation gates
- honeypot safety
- fingerprint consistency
- focus order
- wheel scroll
- drag/drop
DataTransfer - contenteditable selection
- paste clipboard
- native select
- hover dwell
- React value tracker
- keyboard modifiers
- touch events
- stack trace fingerprint
- viewport click coordinates
- pointer continuity
- mousemove rate
- scroll momentum
- intersection visibility
- Shadow DOM controls
- iframe targeting
- file upload
- keyboard Tab navigation
- network/console capture
- dialog handling
- target blank popup
- modal focus trap
- autocomplete combobox
- SPA route change
- strict CSP screenshot/coordinate fallback
- dynamic wait/readiness
- explicit tab lifecycle
- strict CSP eval/snapshot via CDP (regression guard for the CSP bypass)
Design notes
- A failure is useful only when compared to expected mode. Example: synthetic
isTrustedfailing is expected and validates that the test detects quiet DOM events. - Some tests are capability-gated. Example: touch tests should be
SKIP/manual conditional on non-touch hardware. - Fingerprint tests should warn before blocking. Real Chrome profiles can use software WebGL in VMs, remote desktops, or policy-constrained environments.
notes/bypass-ideas.mdis historical guidance for older synthetic-only versions. Prefermanifest.jsonfor current expected outcomes.notes/browsergym-compat.mddefines the reset/step/validate/observation/BID contract for external BrowserGym-style agents.notes/runner-spec.md,notes/scoring.md, andnotes/profiles.mddefine runner output, scoring, retry policy, and environment metadata.