ABROWNFOX001

Posted on Sep 17

Failure Modes That Still Kill Mid-Band 5m Bots

GitHub: https://github.com/abrownfox0/abrownfox001-twap60-prediction-trigger-system

YouTube walkthrough: https://www.youtube.com/watch?v=XzhugRL6BV4

Live profile: https://polymarket.com/@abrownfox001

Part 2 defined the slot log.

Part 3 is the failure catalog that log is supposed to catch. TWAP60 and a 150ms taker delay killed last-tick sniping. They did not make 50¢ trading safe.

1. Stale or Mixed Official Series

Still the first killer.

Bug	What it looks like in logs
RTDS connected, TWAP old	`stale_official = true` but bot still bought
30s open, 60s close	`twap_window_s` disagrees with live market rules
CEX last used as fallback	`resolution_src = missing` plus a fill anyway
Snapshot labels in research	model “works” on a retired target

If the official series is wrong, every later “edge” is fiction. Skip the slot. Do not invent spot.

2. Paying the Mid-Band and Not Getting the Mid-Band

The design only works near 50¢.

Failure mode:

P(up) clears
ask prints 50.5¢
fill lands 53–55¢
delay_ms_assumed = 150

That is not a signal problem first. That is fill-quality tax after the September delay change.

If fill_price keeps leaving the 45–55¢ story, shrink clips, wait longer, or stand down. Do not “add conviction.”

3. Delay-Taxed Decisions

A 150ms crypto taker delay means the idea can rot between signal_ts and fill_ts.

Typical kill pattern:

path looks good
order enters the delay window
official TWAP or the 50¢ book moves
cancel is not a free undo
you own the wrong 50¢

Measure fill - signal before touching weights.

If that gap jumped after Sept 4 and PnL fell with it, retune execution first.

4. Scratch Fantasy on a Thin Book

The public footprint includes ~930 near-zero-spread round trips. That is a depth assumption.

Failure mode:

buy 50.4¢
thesis dies
best bid is 47¢
“breakeven scratch” becomes a 3¢ loss
or the bot holds because it refuses to pay the spread, then dies at $0

Log scratch spread as its own field.

If the scratch distribution leaves ~0, the second edge is gone.

5. Quota Storms Disguised as Risk Management

Volume-tier limits turned cancel-spam into self-harm.

Kill pattern:

panic flatten
20 cancel/replace bursts
429 / Retry-After
slot loop stalls
next live read is missed
log shows rate_limit_hits exploding while action = skip

A specialist that places a few clips per slot should not need a cancel storm. If it does, the state machine is the bug.

6. Frozen Thresholds After the Target Smoothed

60s TWAP is less twitchy than snapshot or 30s TWAP.

Old constants fail in two directions:

scratch too fast on a smoother path
hold too long because the model no longer sees “spikes”

Look at buy/sell clocks. If activity piles back into 0–5s or 270–300s, the lifecycle drifted. That is a failure mode even when PnL has not blown up yet.

7. Scope Creep

This one does not show up as a single bad fill. It shows up as a worse bot.

Examples:

Combos RFQ jammed into engine.ts
ETH/SOL spray because BTC 5m got harder
agent connector becomes the trigger
15-minute weights reused on 5-minute labels

Those failures destroy calibration slowly. The account stops looking like a specialist before the README does.

8. How I Want These Tagged in Logs

Every skip or loss should get one primary tag:

STALE_TWAP
MIXED_WINDOW
FILL_TAX
DELAY_ROT
THIN_SCRATCH
RATE_LIMIT
THRESHOLD_DRIFT
SCOPE_CREEP
SIGNAL

SIGNAL is allowed only after the others are ruled out.

That is the whole point of parts 2 and 3.

9. What Part 4 Covers

Once failures are named, retuning has an order.

Next post: what to change first, which dataset you are allowed to use (post-TWAP60, post-Sept 4 delay), and what must stay frozen while you measure.

Links

Repo: https://github.com/abrownfox0/abrownfox001-twap60-prediction-trigger-system
Video: https://www.youtube.com/watch?v=XzhugRL6BV4
Live activity: https://polymarket.com/@abrownfox001?tab=activity

Not financial advice. Name the failure before you touch the model.

If you have more questions, please feel free to contact me at any time: https://t.me/abrownfox001

My Polymarket Activity: https://polymarket.com/@abrownfox001?tab=activity

#Polymarket #TWAP #TradingBot #BTC #AlgoTrading #PredictionMarkets #RiskManagement

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