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Piano synth · kat-coder-air-v2.5

Using the pre-provided tone.min.js (global Tone), build a playable piano keyboard controlled by mouse and computer keys that synthesizes notes with an ADSR envelope and visual key feedback.

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transcript · 6 messages
user

Using the pre-provided tone.min.js (global Tone), build a playable piano keyboard controlled by mouse and computer keys that synthesizes notes with an ADSR envelope and visual key feedback.

assistant

write /tmp/ws/index.html (14875 bytes)
toolResult

Successfully wrote 14875 bytes to /tmp/ws/index.html

assistant

Let me verify the file is in place:

bash {"command":"ls -la /tmp/ws/index.html /tmp/ws/tone.min.js 2>&1"}
toolResult

-rw-r--r--. 1 node node 15797 Aug 1 20:30 /tmp/ws/index.html -rw-r--r--. 1 node node 349169 Aug 1 20:29 /tmp/ws/tone.min.js

assistant

Done. `/tmp/ws/index.html` is ready alongside `tone.min.js`. **What's included:** - **29 keys** spanning C3–E5 (white + black), laid out like a real piano with black keys absolutely positioned over the white-key borders - **Mouse & touch** — click/drag across keys for glissando, mouseover while held continues playing - **Computer keyboard** — two rows mapped: - Lower octave: `Z X C V B N M` (white) + `S D G H J` (black) - Middle: `A S D F G H J K L ;` (white) + `W E T Y U O P` (black) - **ADSR envelope** — real-time adjustable Attack / Decay / Sustain / Release sliders that update the synth on the fly - **Waveform selector** — sine, triangle, square, sawtooth - **Volume control** (dB) - **Effects chain** — PolySynth → FeedbackDelay → Reverb → Master Volume - **Visual feedback** — keys light up blue (white) or indigo (black) and press down when active - **Audio context start** — a click-to-start overlay satisfies browser autoplay policy

TAKE IT TO CODE

A single self-contained HTML file — copy it and open in any browser, or reuse the prompt with your own pi-agent run.

RUN

modelkat-coder-air-v2.5
vendorKwaipilot
harnesspi-agent
generated2026-08-01

EVALUATION

4/5 working

Click reveals a clean piano synth UI with ADSR sliders and labeled keys; arrows/wasd/space don't play notes as expected but layout looks polished.

Vision grade · anthropic/claude-sonnet-5

MEASUREMENTS

Raw readings from the capture, not a verdict — the grade above is the only judgement. Percentages are how much of the screen changed; the measure under-reports sparse motion on a dark background.

idle motion0.0%
on click91.7%
on drag0.0%
on wheel0.0%
on enter + space0.0%
on arrow keys0.0%
on w/a/s/d0.0%
frame spread68 / 255
console errors0
js errors none

METRICS

runtime31.3s
tokens in16k
tokens out5.9k
cached10k
cost / run$0.0047