Hand off the errand. Check every price.

# Install uv first; replace ... with your provider keys
export OPENROUTER_API_KEY=...   # for Jev and the LLM that plans and reads
# export TYPESAFE_API_KEY=...   # optional: use direct TypeSafe for Jev instead
# export AI_GATEWAY_API_KEY=... # Jev backup; also serves the LLM when OPENROUTER_API_KEY is unset
export BROWSER_USE_API_KEY=...  # the cloud browser; or pass --local to use Chrome

uvx fastbrowse "What is the title of the top story right now?" \
  --start https://news.ycombinator.com/

# Without a starting page, fastbrowse proposes the first address from the task
uvx fastbrowse "Find the httpx package on PyPI and report its latest released version."

# Authorization gates and a secret the model only ever sees by name
export SAUCE_PASSWORD=secret_sauce  # public practice credential
uvx fastbrowse "Log in as standard_user and add the backpack to the cart." \
  --start https://www.saucedemo.com/ \
  --secret password=SAUCE_PASSWORD \
  --authorize

# uv tool install fastbrowse  # keep fastbrowse on PATH
# uv add fastbrowse           # or put it in a project

# uv add fastbrowse
# Set the OpenRouter key shown in CLI usage; with no browser given, this runs local Chrome.
import asyncio
from pydantic import BaseModel
from fastbrowse import run_task
from fastbrowse.models import Limits

class Release(BaseModel):
    package: str
    version: str

async def main() -> None:
    result = await run_task(
        "Find the httpx package and report its name and latest released version.",
        start="https://pypi.org/",
        output_schema=Release,
        limits=Limits(max_dollars=0.10),
    )
    if not result.succeeded:
        print(result.status, result.error)
        return
    release = Release.model_validate(result.data)
    print(release.package, release.version)
    for citation in result.citations:
        print(citation.quote, citation.deep_link)

asyncio.run(main())

// npm install fastbrowse zod
// Node.js 20 or newer. No Python and no uv on the machine.
// The npm package installs the native binary for your platform.
// Set OPENROUTER_API_KEY in the environment for Jev and the planning LLM.

import { Fastbrowse } from 'fastbrowse';
import { z } from 'zod';

const Release = z.object({ package: z.string(), version: z.string() });

const fb = await Fastbrowse.start({ local: true });
try {
  const result = await fb.run('Find the httpx package and report its name and latest released version.', {
    start: 'https://pypi.org/',
    output: Release,
    limits: { maxDollars: 0.1 },
    onEvent: event => {
      if (event.type === 'step') console.error(event.step.operation, event.step.target);
    },
    signal: AbortSignal.timeout(120_000),
  });
  console.log(result.status, result.answer);
  if (result.status === 'complete') console.log(result.output.package, result.output.version);
  for (const evidence of result.evidence) console.log(`  "${evidence.quote}" from ${evidence.url}`);
} finally {
  await fb.close();
}

# Working on fastbrowse itself
git clone https://github.com/agent-labs-dev/fastbrowse.git && cd fastbrowse
uv sync --all-extras && cp .env.example .env
# Fill in .env with an OpenRouter key; live runs also need BROWSER_USE_API_KEY.

# Run the fixture evaluation suite
uv run python -m fastbrowse.evals.runner

# Compare task success, time and cost using the published benchmark methods.
# Open Benchmarks on this site for the comparison methods.

# Lint, types, tests
uv run ruff check . && uv run ty check && uv run pytest