How to use Codex to build a card-controlled music player
An author worked with Codex on a card-controlled phone music player, supplying a depth-camera idea that resolved a conflict between NFC scanning and a blank playback screen.
news.ycombinator.com
Suggested prompt
Suggested prompt written by Agents In Use, not the source author. Replace bracketed inputs and review tool permissions first.
Help build a card-controlled music player on [phone]. Use [NFC card mapping] to select music and remember playback positions. Explore depth-camera detection for card removal so [blank-screen swipe controls] can remain available during playback.
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See placements →Evidence at a glance
Sourced account- Source poster / publisher
- jonplackett
- Original account
- Read the source ↗
- Published
- Source link checked
- Reported result
- The author reports a working player that starts and resumes music when cards are placed on the phone and stops playback when a card is removed.
- Human involvement
- The author researched feasibility, specified the interface and intervened when Codex could not resolve the NFC behavior.
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How the agent did it
- Research the interface and technology stack, then write a detailed Codex brief.
- Iterate with Codex for about two hours on the player.
- Propose depth-camera detection to control when the NFC scanning interface returns.
The author used Codex to build a phone-based music player controlled by physical cards. Before prompting, they thought through the interface and technology stack, researched what would work, and wrote a detailed brief. They report that the player worked after about two hours of discussion and reconsideration.
A specific interaction caused trouble: the phone needed its NFC interface visible while looking for cards, but the author wanted a blank screen during playback. A hole in the surrounding box would let the listener swipe that screen to skip backward or forward. The author says this problem stumped Codex.
They then proposed using the depth camera to detect a card placed on the phone and showing the scanning interface again only when the card was removed. In the reported result, placing a card starts music and restores its song and playlist position. Removing the card stops playback when the phone detects a few centimetres of clearance. Replacing that card, or another, resumes its saved position.
Who it's for: Makers designing physical controls around a phone-based media player.
Prompt
Suggested prompt (written by Agents In Use, not the author's)
Source: Hacker News · jonplackett
Frequently asked questions
How did the author solve the NFC interface problem?
The author proposed using the depth camera to detect cards on the phone, then restoring the NFC scanning interface only when a card was removed.
What playback behavior did the author report?
Placing a card starts music from its remembered song and playlist position. Removing it stops playback, and replacing it or another card resumes the corresponding saved position.
More details
Remaining steps
- Implement the reported card placement, removal and playback-resume behavior.
About this account
Codex worked through a detailed brief and iterative discussion; the author supplied the idea that resolved the reported interaction problem.
Platform: Hacker News. Attribution: https://news.ycombinator.com/item?id=49933568. Prompt: Suggested (written by Agents In Use, not the author's). Sourced by the Agents In Use pipeline.
Credit: jonplackett on Hacker News
Source published
Added to Agents In Use
Source checked
Tools and topics
Codex · Phone NFC · Phone depth camera
Music player · NFC · Physical interfaces
Editorial completeness: 100/100. Measures documented fields, not agent performance or verified outcomes.