Skip to content

Build a Magic: The Gathering pauper decklist browser with player profiles

Session from merchantscroll-traces on Hugging Face by vedalken · MIT · condensed by Coders Talk

3msession
2interventions
GOAL

Implement a set of planned features (decklist export, Pauperwave archetype naming/classification, Pauperwave IRL decklist import, player profile page) for a Pauper decklist browsing site, one feature at a time with developer review after each.

  1. Prompt · +0
    Read the SOW and feature docs, implement features one by one, run a local server so I can review each before confirming or asking for changes.
  2. Agent did · +0m
    Fixed the export decklist filename format to match spec and started a local HTTP server on port 8080 so the developer could review the site live.
  3. Agent did · +0m
    Built a first archetype classification engine: created archetypes/pauper.json from card frequency analysis of raw tournament data, added signature-card matching, and displayed archetype names in the deck header, dropdown and export text.
  4. Intervention · +0m
    Told the agent the deck labeling was wrong but to keep moving to the next feature and leave this one marked open rather than complete.
    Why: The classification was guessing from card frequencies without real labeled data, so I didn't want it marked done yet.
  5. Agent did · +0m
    Built a Pauperwave crawler (src/pauperwave_crawler.py) parsing the markdown decklist format, integrated it into the pipeline, imported 63 IRL tournaments, added an 'IRL' badge to the UI, and wired the crawler into the GitHub Actions workflow.
  6. Intervention · +1m
    Asked the agent to revert the 4-of card highlighting feature entirely and mark it cancelled since they weren't sure yet how they wanted it to work.
    Why: I didn't know how I wanted this feature to look yet, so I'd rather cancel it than leave a half-right implementation in.
  7. Agent did · +1m
    Rebuilt the archetype taxonomy from 567 real labeled Pauperwave decklists instead of guesswork, wrote a classifier module, and backfilled archetype labels onto 15,679 MTGO decklists.
  8. Agent did · +1m
    Implemented the player profile feature end to end: a Python stats pipeline generating per-player JSON (trophies, win rate, favorite decks, recent results) and a new player.html page, plus clickable player names and swipe/arrow navigation between deck and profile.
  9. Fail · +3m
    After converting the profile page into an in-page modal, the developer reported the modal never appeared; the agent found the modal element lived inside #content, which was wiped by innerHTML="" on every deck navigation, and moved it outside that container to fix it.
  10. Outcome · +3m
    Session ended with all six planned features resolved (5 done, 1 explicitly cancelled), a working Pauperwave-based archetype classifier backfilled across ~15,679 decks, a player profile modal, and refined header/stats UI, confirmed working by the developer.
VERDICT

Next time I'd start by pointing the agent at real Pauperwave labeled data before letting it guess archetypes from card frequency — that guesswork produced a whole feature I had to mark 'keep open' until we redid it properly. The correction that did the most work was telling it to cancel the card-highlighting feature outright instead of half-shipping it, and later catching that the profile modal was being wiped by an innerHTML reset, which the agent found and fixed once I reported the symptom.

I tried this · 0

Discussion · 0

How Builds work