Arpeggiator pad · gpt-oss-20b

Using the pre-provided tone.min.js (global Tone), build a clickable pentatonic pad grid that triggers a synth voice with reverb, plus a play/stop button that runs an arpeggiator sequence at an adjustable tempo. All sound synthesized, no audio files.

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transcript · 4 messages

user

assistant

thinking

We need to create index.html that includes tone.min.js in same dir. The root has tone.min.js. Provide a clickable grid, say 5x3? Pentatonic pad grid meaning scale notes? Pentatonic scale: C major pentatonic: C D E G A. Could map to grid 5 columns 2 rows. Each cell clickable triggers synth note with reverb. Synth voice could be PolySynth or Omni? Use Violin-like synth? But simple: Use Tone.Synth with Wave. Use Reverb. On click, trigger synth to play note for short duration.

Also play/stop button to run an arpeggiator sequence at adjustable tempo: use Tone.Transport with sequence.

Thus we will create index.html with inline CSS and JS.

Need to load tone.min.js with <script src="tone.min.js"></script>.

Inside script, create synth: new Tone.Synth({ oscillator: { type: 'sine' }, envelope: { attack: 0.01, decay: 0.2, sustain: 0.5, release: 1 } }). connect to reverb => reverb.connect(Tone.Destination).

Also a grid output: maybe each cell is a div button inside a container grid display: using CSS grid.

Number of cells 5x2 grid. Map notes: C4, D4, E4, G4, A4. Put note mapping in array.

Implement click handler: trigger synth.triggerAttackRelease(note, '8n');.

Play/stop button: controlling Tempo: Use Tone.Transport.start()/stop() ; Sequence: new Tone.Sequence(function(time, note){ synth.triggerAttackRelease(note, '8n', time); }, notes, '4n'); // or bigger? Use adjustable tempo: maybe input slider for BPM, and display. Let's provide a range input slider 60-180, update Tone.Transport.bpm.value.

Add button play/stop toggled.

Clickable pad grid triggers synth even when arpeggiator playing? It should play independently, as synth is polyphonic.

With Tonal's Tone.js library loaded, need to wrap use of global Tone.

All code in index.html: <html><head><meta charset="utf-8"><title>Pentatonic Pad</title> <style>... grid styling...</style> </head> <body> ... grid container, buttons ... <script src="tone.min.js"></script> <script>... JS... </script></body></html>

Output must create index.html file.

Let's draft final answer. Then use 'write' tool to create file index.html.

Let's produce content.

→ write index.html (4195 bytes)

toolResult

Successfully wrote 4195 bytes to index.html

assistant

thinking

We wrote index.html. Need to ensure reverb effect is actually attached: we connected synth to reverb, but reverb then to destination incorrectly. In current code: synth.connect(reverb); reverb.toDestination(); Actually we wrote const reverb = new Tone.Reverb(...).toDestination(); and then synth.connect(reverb); That would cause reverb to have its own destination, not reverb to forward to. In Tone.js, connecting a node to reverb that is already sending to destination will cause two outputs? Actually reverb is an AudioNode. If we call reverb.toDestination(), it will connect its output to destination. Then we connect synth to reverb - that's good. But synergy: reverb must be after synth. So synth.connect(reverb) and reverb.toDestination() fine. Wait we created reverb with toDestination, then connect synth to reverb. So synth feed to reverb to dest. Good.

Arpeggiator: used Tone.Sequence but not attached to transport? We started with .start(0), but we need it to sync to Transport. Tone.Sequence is a Transport node that will tick with Transport. Start on start. Good.

Need to use playStop to control transport. Good. But ensure the sequence is paused when transport stops; it's automatic.

Test: suc. However we didn't enable reverb preDelay; fine.

We may want to set the reverb's decay after connecting to dest at start? Works.

We may also need to call Tone.Transport.start() only once (!). It's fine.

One issue: we used <script src="tone.min.js"> but we don't know the file path; the file is pre-provided named tone.min.js. In root folder. That's correct.

Need to ensure we have a correct version of Tone that supports Sequence: yes.

But better to control the arpeggiator start only when playing. Actually the sequence will start independent; we can toggle transport. It's okay.

We might need to set reverb automatically. Also E release time in synth envelope. Good.

But we may want to show logs or interactive.

Maybe we should also handle not double starting of Device on page load. We call start at sequence start, but not start transport until user plays. That's okay.

Potential missing: we didn't set any global context to start on user interaction due to autoplay restrictions. We call resume inside click. Good.

Let's run linter: grid plus notes array length 5. style ok.

Potential bug: Using Tone.Sequence, but we set .start(0) - That expects time param? Actually Tone.Sequence expects .start(0). Good.

But we didn't connect reverb after creation of synth. We connect reverb later. Should reverb catch before destination? fine.

Now confirm that notes triggers on clicking: synth.triggerAttackRelease(note,"8n") means 8n from synth node not attached to Reverb? The synth is connected to reverb, so sound output passes through reverb. Good.

Arpeggiator uses synth.triggerAttackRelease(duration "16n") each step. Good.

Now confirm file saved length. index.html created.

Potential improvement: import Tone as global: we used new Tone.Synth, fine.

All requirements satisfied: building clickable pentatonic pad grid triggers synth with reverb; play/stop button runs arpeggiator at adjustable tempo. All in single file.

Let's provide final answer.

The single‑page web app has been created and saved as **`index.html`** in the current directory. Open the file in a browser to interact with the pentatonic pad grid and the arpeggiator controls.

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

modelgpt-oss-20b

vendorOpenAI

harnesspi-agent

generated2026-07-22

EVALUATION

★★★★★ 2/5 partial

Simple pentatonic pad grid with play/BPM slider renders, but no visible reaction to click, drag, or keys.

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 click0.0%

on drag0.1%

on wheel0.0%

on enter + space0.0%

on arrow keys0.0%

on w/a/s/d0.0%

frame spread12.9 / 255

console errors0

js errors none

METRICS

runtime15.1s

tokens in1.5k

tokens out2.5k

cached2.3k

cost / run$0.0004