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TRAINING FLOOR · 5 DECKS · 54 DRILLS

The Gym

Reading is half the work — here you write the prompt and the prompt gets graded. The Prompt Katas deck hands you a real work brief and a source document; you write the full prompt, an instant five-anchor analysis marks ROLE / CONTEXT / FORMAT / CONSTRAINTS / EXAMPLES pass-or-miss, an optional bring-your-own-key deep grade puts Claude in the examiner's chair, and the model solution opens like a LeetCode editorial. Around it: concept drills, back-of-envelope numerics, and Python katas on a real interpreter. No account, no backend of ours — nothing you type leaves your browser except the deep grades you explicitly send to Anthropic with your own key.

FORMATSPROMPT KATA · MCQ · NUMERIC · PYTHON GRADINGCLIENT-SIDE + OPT-IN BYOK JUDGE BEST RUNSSAVED LOCALLY SHAREPNG RESULT CARD
G.1

Pick a deck

One attempt per question — keys 1–4 answer, Enter advances, and SKIP counts as a miss. Code katas allow unlimited runs until the tests pass; prompt katas grade your written prompt against the five anchors (≥ 4/5 clears) and then show the editorial. Answer options are shuffled every run, so read — don't pattern-match. The clock runs for the whole deck, every explanation teaches something the question couldn't, and your best score per deck persists in this browser. Miss something? The end screen lets you re-run just your mistakes. Clear a deck, download the card, post it.

NOTE

Code katas run on Pyodide + numpy — a real CPython compiled to WebAssembly, lazy-loaded (~10 MB) the first time you hit RUN & GRADE. Your code plus the visible test asserts execute locally; passing means your stdout ends with ALL TESTS PASSED. Prompt-kata deep grades are strictly bring-your-own-key: the request goes from your browser straight to api.anthropic.com, the key lives in this tab's sessionStorage only, and skipping the deep grade costs you nothing — tier-1 grading is fully offline. If a numeric drill stalls you, the relative tolerance is printed under the input — estimate, don't agonize.