How we test

CrewAI and Browser Use with a hosted Grok model: scored hands-on test

Test date 2026-10-14 · Tools: CrewAI, Browser Use

Verdict in one line: with a hosted model, both frameworks did the job. CrewAI got the credit-control task fully right 3 out of 3 times for about £0.0012 a run. Browser Use read GOV.UK correctly 3 out of 3 times for about £0.012 a run, but only after we changed one setting: its default request parameters are rejected by xAI’s API. Scores: CrewAI 86/100, Browser Use 79/100.

This follows our local-model test, which we left unscored because a 3B CPU model failed the tasks. The tasks here are identical. Only the model changed.

Setup

Modelgrok-4.20-0309-non-reasoning via xAI’s OpenAI-compatible API (https://api.x.ai/v1). We chose it from the /v1/models list as the cheapest current general-purpose text model. grok-build-0.1 is cheaper but aimed at coding.
Price (official, docs.x.ai/docs/models, checked 14 Oct 2026)$1.25 per 1M input tokens, $0.20 per 1M cached input, $2.50 per 1M output (prompts under 200k tokens)
Exchange rate1 USD = £0.75377, ECB reference rate for 14 Oct 2026 via frankfurter.app
Versionscrewai 1.15.28, browser-use 0.13.11, Python 3.12, same virtualenvs as the local test
Cost basisToken counts from each framework’s own usage report, multiplied by the prices above (cost sheet)

Test 1: CrewAI, UK credit-control task (3 runs)

Same task, data and prompt as before (CSV). The only code change is the LLM(...) line, which now points at xAI with temperature=0 (script). Correct answer: INV-101, INV-102 and INV-105 overdue, £3,150.60 gross overdue, chaser to Tyne Accountants for £1,170.60.

CheckRun 1Run 2Run 3
VAT and gross for all 5✅✅✅
Overdue list (101, 102, 105)✅✅✅
Total gross overdue £3,150.60✅✅✅
Chaser to Tyne Accountants, INV-105, £1,170.60 gross✅✅✅
Any wrong extra figures (e.g. days overdue)nonenone (“44 days”, correct)none (“44 days”, correct)
Wall time3.7 s3.7 s3.7 s
Tokens (in / cached / out)514 / 128 / 452514 / 512 / 455514 / 128 / 457
Cost$0.00164 (£0.00123)$0.00124 (£0.00094)$0.00165 (£0.00124)

Logs: run 1, run 2, run 3. Each run made one model request.

Test 2: Browser Use, read GOV.UK VAT rates (3 runs)

Same task text, headless Chrome, max_steps=8, vision off (script). Correct answer: standard rate 20%, reduced rate 5%, as on gov.uk/vat-rates.

First attempt failed 3/3 because of configuration, not the model. Browser Use’s ChatOpenAI sends frequency_penalty=0.3 by default, and xAI returns HTTP 400 “does not support parameter frequencyPenalty”. Each run hit 6 errors and stopped after 5 consecutive failures, with no result (log 1, 2, 3). We found the default in Browser Use’s source and set frequency_penalty=None. That was the only change. Those rejected requests reported 0 tokens, so we’ve counted them at $0.

CheckRun 1Run 2Run 3
Called done, is_successful() True✅✅✅
Standard rate 20%✅✅✅
Reduced rate 5%✅✅✅
Steps222
Wall time6.6 s7.4 s8.8 s
Tokens (in / cached / out)11,986 / 256 / 63211,946 / 256 / 74211,902 / 256 / 839
Cost$0.01629 (£0.01228)$0.01652 (£0.01245)$0.01671 (£0.01259)

Logs: run 1, run 2, run 3. Browser Use costs about 10x more per run than CrewAI because it sends the page’s DOM, about 6,000 prompt tokens per step.

Comparison with the free local model (same tasks)

Qwen2.5 3B local (CPU)grok-4.20 non-reasoning (hosted)
CrewAI checks passed1 of 44 of 4, in 3 of 3 runs
CrewAI time40.6 s3.7 s
Browser Use resultnever finished (256 s, JSON schema errors)correct in 2 steps, 3 of 3 runs
Cost per run£0£0.001 (CrewAI), £0.012 (Browser Use)

Scores (rubric)

These scores cover what this test exercised: the framework, run locally, driving one hosted model on one task each. Where a criterion wasn’t exercised, we gave partial credit and said why.

Criterion (weight)CrewAIBrowser Use
Task success (30)30: every check passed in all 3 runs30: correct in all 3 runs (once configured)
Autonomy & reliability (20)18: no intervention and no failures. −2 because the totals are free-text arithmetic with nothing checking them15: no intervention once working. −5 because the default config failed 3/3 against xAI
Setup & ease of use (15)14: install about 20 s, one-line model switch. −1 for needing LiteLLM’s openai/ prefix11: install about 20 s, used existing Chrome. −4 because the 400 error meant reading library source to find the fix
Value for money (15)15: open source (MIT), about £0.0012 a run14: open source (MIT), about £0.012 a run. −1 for 10x the token use per task
Safety & control (10)5: the agent only drafted (no send tool). We didn’t exercise an approval step5: read-only task. Stopped itself after 5 consecutive errors. No approval gate exercised
Integrations (10)4: verified with Ollama and xAI (OpenAI-compatible) only. No SMB app connectors tested4: verified with local Chrome plus Ollama/xAI only
Total86 / 10079 / 100

Caveats

Raw evidence files are linked inline and hosted under /evidence/2026-10-14/.