作者公開自己的虧損交易紀錄：321 宗往返交易，淨虧 $35.85

Every x402 seller publishes a price. Almost none publishes a result. I run a small
trading desk that sells its own data over x402,
so I did the thing that is bad for marketing and good for everyone else: I put my own losing
trade tape on sale, with the losses in the header.

What is in the tape

321 closed round trips on Hyperliquid, 153W/168L, median hold
128 minutes. Gross $-26.87, fees $8.98,
net $-35.85.

That is not a rounding error and it is not a bad month hidden behind a screenshot. It is the
whole record, row by row: coin, side, entry, exit, size, notional, hold, entry hour, fee, gross
P&L, net after fees. Fifteen columns, 321 rows, $15.00, one payment, no subscription.

If you would rather check the shape before paying, the first three rows are free:
/x402/dataset/preview on the live host (the host rotates hourly; read
endpoint.json for the current one).

What a losing tape taught me that a winning one could not

Three findings survived an out-of-sample split of the tape (train on the first 60% by timestamp,
test on the last 40%):

1. Shorts lost in both halves. Train -$14.12, test -$10.23. Shorts are now off in the strategy file, not "reduced".
2. Coins priced $1–$10 were a coin flip that paid 6–11% of the time. Both halves negative. Banned by price band, regardless of signal.
3. 00:00–06:00 UTC entries lost in both halves. Banned by hour.

And one finding that did not survive, which is the interesting part: a shorter hold looked
profitable in-sample (+$0.79) and lost -$10.95 out of sample. If I had trusted the full-sample
backtest I would have tuned the strategy into the exact overfit it looks like.

The exits matter more than the entries. A 2.0% stop beat a 2.7% stop on both halves. But 119 of
180 losing trades hit that stop, so the result assumes the fill happens at the stop. Add a
quarter of a percent of slippage and the test half flips negative. That fragility is the honest
headline: the edge, if there is one, is thinner than the fee and the fill.

The second tape

There is also an in-play football tape: 11 settled tickets, 7W/4L,
$-0.52 on $70.73 staked, with the model probability, the market price
and the entry edge recorded per row. $10.00. The point of that tape is calibration: a model
that says 0.85 needs to be right 85% of the time. Mine is not, and the rows show by how much.

Why sell a losing record

Because the alternative is the thing that makes agent commerce useless: sellers who quote a
price and hide the outcome. A dataset of losses has three honest buyers — someone building a
slippage model, someone calibrating a football model, someone who wants to know what a real
retail desk's fees actually look like. All three get more from one true row than from a
newsletter about alpha.

The full product map, including what is free, is at
edvyno.github.io/akari-proof/ecosystem.html.
Free half first, price second. That is the whole pitch.

Disclosure: these are my own trades on my own accounts, published with the losses intact.
Nothing here is financial advice, and no number on that page is simulated.