new·The score now tells you which way it movedA brain's exam only ever grows: its own material writes questions, and so does every question a real caller asked and did not get answered. The score is a percentage over that growing set, so a brain that learned more could post a smaller number — and this week three did. One of them answered two MORE questions than the week before and showed eighteen points less. Printed as a single percentage, that reads as decline to a reader and as punishment to anyone who contributes material.all news →
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Vitest

Answer questions about testing with Vitest as documented today: writing tests and assertions, mocking with vi, the config file and every option, coverage providers, browser mode, workspaces, the CLI and its flags — the current API, not an earlier major's.

3,397 notes across 4 brains · updated 2026-08-09 · trained 79%

since last sitting: +77 newly passed — this brain is learning · the verified changelog →

use this brain
# sign in to get a token
$ claude mcp add --transport http mozg \
https://mozg.sh/mcp --header "Authorization: Bearer …"
> use mozg/vitest — …
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Ask it things like

answers 77/100 on its latest exam
How do you access the vi object in Vitest?Mocking with vi✓
How do you use test.each to run a test with multiple datasets?Writing Tests & Assertions✓
What does vitest run command do?CLI & Commands✓
What does clearMocks do?Configuration File & Options✓
What is the minimum Vitest 5.0 version of Vite required?Configuration File & Options✓
What does setupFiles configuration do?Configuration File & Options✓
What does globals option control?Configuration File & Options✓
What are the two coverage providers Vitest supports?Coverage✓

What is inside

asking this brain searches all 3
Vitest · API referenceAnswer questions about the Vitest API exactly as specified: describe, test, expect and the vi object with every method's signature, and every assertion matcher with its behaviour.1081 notes86%Vitest · Config referenceAnswer questions about Vitest configuration exactly as specified: every test, coverage, browser, pool and reporter option with its name, type and default value.709 notes53%Vitest · GuideAnswer questions from the Vitest guide: writing and running tests, mocking functions, modules and timers with vi, snapshot testing, coverage, browser mode, workspaces, test context and the CLI commands with their flags.1607 notes84%

What it can answer

100 coverage checks
79%
Answers 77 of the exam's 100 questionsIt answers 77 questions, 77 more than last time, out of an exam that grew by 100.Nothing it used to answer has stopped working.
▲Configuration File & Options24 / 36
▲Browser Mode16 / 20
✓Mocking with vi14 / 14
▲CLI & Commands9 / 11
▲Writing Tests & Assertions9 / 10
▲Coverage5 / 9
exam badge — share this score →

Attacks survived

re-run weekly · 2026-08-09
✓gate-battery12/12 known hostile payloads caught by the ingest gate
✓injection-corpusevery active note scanned — no steering language
✓secret-corpusevery active note scanned — no keys or credentials

heuristic scans against known attack classes — measured and dated, not a promise of unpoisonability

Inside

    Licence

    CC BY-NC-SA 4.0

    Use it, copy it, build on it, with credit. Selling it is not allowed.