The venue's own daily trade tape plus a per-market census. trades.csv is every executed trade — timestamp, product, league, market type, straight-vs-parlay, legs, price, size. markets.csv is one row per market per day: open interest, daily volume, OHLC, status.

Use it for: The only venue where we MEASURE volume from the trades rather than repeat a claim. Parlay economics, product mix, per-market price history. Open interest is published but not yet trusted — it swings 9x on consecutive days, likely daily-settling baseball.

First-party, direct from the exchange's own S3 (cert + AmazonS3 headers verified — no aggregator). clearing/outbound/mkt_eod_YYYYMMDD.csv is per-contract daily volume, OI, block volume, settlement price and OHLC. exchange/outbound/trade_data/trades_eod_YYYYMMDD.csv is the tick tape with nanosecond timestamps. The two cross-validate exactly.

Use it for: Measured Rothera volume, replacing the Artemis estimate. WARNING: 83.1% of all volume ever traded there is World Cup markets, so any average spanning Jun-Jul describes a tournament, not a venue. Post-tournament baseline is ~$14.8M/day. Root page is a static index = the manifest; directory paths 403.

Kalshi's own published end-of-day report, one object per market per day. ~1.1GB uncompressed, so it must be streamed rather than parsed. Volume and OI are CONTRACT COUNTS, not dollars.

Use it for: Our deepest venue history and the source behind the modelled fee series and the combo split. The dollar figures are ours (OI x each market's own price), never a flat $1.

Live markets, prices, 24h changes, USD volumes, liquidity. No key required.

Use it for: Powers the Markets page on this site. The reference for anything live on Polymarket.

Live events and markets, prices, volumes. Public read access, no key. Gotcha: use /events?with_nested_markets=true — the /markets endpoint is parlay junk.

Use it for: Powers the Kalshi side of the Markets page. Volume is contract count, not USD — normalize before comparing.

Play-money prediction markets. Free API, no key.

Use it for: Sentiment on questions real-money platforms can't list. Never mix into $ volume rankings.

Funding rounds and raises across crypto, including prediction-market companies.

Use it for: The planned live Raises tracker. Key already on hand (Basic tier).

Undocumented but public endpoint returning venue-wide open interest in USD, and accepting a comma-separated market list for per-market OI in one round trip.

Use it for: The only measured Polymarket OI figure. A day not recorded is lost for good — cron it.

Q2 2026 PRESENTATION slide 5, 'Annualized Volume Traded', split consumer / market maker / total, Dec-25 to Jul-26: $0.1bn rising to $11.0bn (July: $3.6bn consumer, $7.4bn market maker). Nothing in the 10-Q or press release — Prediction Markets revenue is folded into Sports Revenue.

Use it for: The only DraftKings volume that exists. TWO TRAPS: the figure is ANNUALIZED (monthly x 12), never a quarterly handle; and 67% of it is market makers, not customers. Check the deck, not the filing.

Platform-level volumes, open interest, fees and users across 7+ prediction-market platforms (Kalshi, Polymarket, Opinion, Predict.fun, Limitless, Myriad, Drift). Daily history going back months.

Use it for: Volume league tables, platform growth charts, the daily Pulse. The single best cross-platform volume source.

SQL-queryable onchain data with thousands of community dashboards — Polymarket wallets, volumes, market breakdowns, trader P&L.

Use it for: Deep onchain questions about Polymarket that no API answers directly. Search for existing dashboards before building anything.

TVL and volume for onchain protocols, including a prediction-market category. Open API, no key.

Use it for: Quick TVL/volume sanity checks and cross-referencing Artemis numbers.

Institutional crypto data dashboards, including prediction-market charts.

Use it for: Chart-ready reference figures for reports; good for citing a third-party source.

Polymarket-specific community analytics — whales, volumes, market activity.

Use it for: Polymarket color that the official API doesn't surface (who's trading, size of bets).

Directory of 140+ prediction-market projects (chain, mechanism, status) plus a cross-platform market browser.

Use it for: Ecosystem mapping and checking we haven't missed a platform. Also a design reference for this site.

Reads DraftKings' own JSON content API rather than rendering the site. Returns category, league, eventName, marketTitle, marketId, americanOdds, decimalOdds, impliedProbability, outcomes[], eventTime, participants. Sports plus crypto, econ, stocks, commodities, politics.

Use it for: PRICES, NOT VOLUME — it answers 'what is DraftKings quoting', never 'how big is it'. Its value is cross-venue price comparison, the asset our build standard ranks #1. $40/1,000 results, so not something to loop. Try DraftKings' underlying JSON endpoint directly first.

The ecosystem atlas: 125 platforms organized by 12 market mechanisms, a mechanism-by-chain matrix showing where nobody is building, a side-by-side compare tool, and 90 tagged industry concepts.

Use it for: Understanding how the ecosystem fits together — mechanisms, taxonomy, gaps. A design reference for this site's Phase 2 and 4.

The knowledge hub: 240+ curated articles and resources, each tagged by concept (information aggregation, oracle design, regulatory arbitrage), plus News, a Forum, and an Ask section.

Use it for: Reading and research. The best place to go deep on the ideas behind prediction markets, and to find the canonical writing on any concept.

Hourly classified prediction-market news archive (posts_archive.jsonl) + daily Artemis-powered Pulse. Runs on GitHub Actions, posts to @predictedupdates.

Use it for: Feeds the News wire on this site. Local clone: ~/Projects/predicted-news-bot/

Fetches daily PM volume for 7 platforms from the Artemis API into CSV/PNG (fetch_volume.py).

Use it for: Report charts. Lives at ~/Downloads/Pricedin/artemis-volume/ — key stays there, not in this repo.

Rothera offers FCMs 'standard FIX API access for order entry and market data' and market makers 'direct market access via FIX API', plus SFTP and reference-data download. No REST API exists — every api./data./md. subdomain fails to resolve. Docs at docs.rothera.io are password-protected (ReadMe, subdomain still 'miaxdx').

Use it for: Not usable by us today. Logged so nobody re-runs the search. Access is institutional onboarding, not a developer signup — it needs Omar to ask them.