Polymarket Coffee Trader

Trades Polymarket coffee markets using three compounding seasonal edges unique to the global coffee market — Brazil frost window mispricing, harvest cycle awareness, and ENSO phase (La Niña/El Niño). Conviction scales with distance to threshold and a seasonal bias multiplier that peaks in July (peak Brazil frost risk) and compresses in October–April when frost is meteorologically impossible.

Coffee Seasonal Trader

This is a remixable template The default signal requires no external API — it uses date-derived seasonal multipliers (frost calendar, harvest cycle, ENSO phase) applied on top of standard price-threshold conviction sizing. The skill handles all the plumbing (market discovery, trade execution, safeguards). Your signal provides the alpha.

Strategy Overview

Coffee is one of the world's most weather-sensitive commodities — and one of the most predictably seasonal. Three structural patterns repeat every year, and Polymarket participants systematically misprice all three:

1. Brazil frost window — Commercially damaging frost in Brazil's coffee belt (Cerrado Mineiro, Sul de Minas, Mogiana) is only physically possible during June–August. Polar air masses (friagens) push north from Patagonia into Brazil's southern highlands exclusively in winter. Yet retail traders price frost optionality into coffee price markets year-round. A market asking "will arabica hit $5?" in January embeds a frost premium that cannot materialize for six more months. We fade it. In July, we back the same trade at higher conviction.

2. Brazil harvest cycle — The main arabica harvest runs April–September. Post-harvest (October–January), supply is at its seasonal peak and well-understood by the market — price spike markets are overpriced. Pre-harvest (February–March), inventory draws down and supply anxiety is legitimate.

3. ENSO phase (La Niña / El Niño) — La Niña brings drought stress to Brazil's coffee belt, tightening arabica supply. El Niño brings excess rainfall to Vietnam, disrupting Robusta logistics. Current ENSO phase is set via SIMMER_ENSO_PHASE env var (update quarterly from NOAA).

The Core Insight: Frost Optionality Has an Expiry Date

The single most important edge in this skill:

text

Brazil frost is only possible in June, July, August.

A coffee price spike market in October through May contains frost
optionality with zero meteorological value.

Retail doesn't know this. They price "could there be a frost?" as a
year-round background risk. We know the frost calendar.

The historical record confirms: every major Brazilian coffee frost event (1975, 1994, 1997, 2000, 2021) occurred between June 15 and August 31. None have occurred outside this window in the modern record.

This gives us a clean seasonal on/off signal:

Period	Frost possible?	Our adjustment
July	Yes — peak risk	1.30x conviction
June / August	Yes — shoulder	1.15x conviction
May / September	No — but market transitioning	1.05x
October – April	No — meteorologically impossible	0.80x (fade frost premium)

Signal Logic

Default Signal: Conviction-Based Sizing with Coffee Seasonal Bias

1. Discover active coffee markets via keyword sweep (prices, crop, weather, futures)
2. Gate: must be a genuine coffee market (_is_coffee_market)
3. Gate: spread ≤ MAX_SPREAD, days to resolution ≥ MIN_DAYS
4. Compute coffee_seasonal_bias(question) = frost_mult × harvest_mult × enso_mult, capped 0.65–1.40x
5. Conviction = (threshold - p) / threshold × bias (YES) or (p - threshold) / (1 - threshold) × bias (NO)
6. Size = max(MIN_TRADE, conviction × MAX_POSITION)

The Three Multipliers

Frost window multiplier (date-derived, no API needed):

Month	Label	Multiplier
July	JULY(peak-frost)	1.30x
June, August	FROST-SHOULDER	1.15x
May, September	FROST-MARGINAL	1.05x
October – April	NO-FROST	0.80x

Harvest cycle multiplier:

Period	Label	Multiplier
February – March	PRE-HARVEST	1.10x
April – June	HARVEST-START	1.05x
July – September	HARVEST-PEAK	1.00x
October – January	POST-HARVEST	0.90x

ENSO multiplier (set via SIMMER_ENSO_PHASE):

ENSO phase	Market type	Multiplier
la_nina	Arabica / Brazil	1.15x (drought stress → bullish)
la_nina	Robusta / Vietnam	1.00x (neutral)
el_nino	Robusta / Vietnam	1.15x (logistics disruption → bullish)
el_nino	Arabica / Brazil	1.00x (mixed)
neutral	Any	1.00x

Combined Examples (TODAY: March 22, 2026 — neutral ENSO assumed)

Scenario	Frost	Harvest	ENSO	Final bias
Arabica price spike — March, neutral	0.80x	1.10x	1.00x	0.88x
Brazil frost event — July, La Niña	1.30x	1.00x	1.15x	1.40x cap
Robusta supply — October, El Niño	0.80x	0.90x	1.15x	0.83x
Arabica production — June, neutral	1.15x	1.05x	1.00x	1.21x

How Sizing Works

With defaults (YES_THRESHOLD=38%, MIN_TRADE=$5, MAX_POSITION=$30):

Price p	Conviction (no bias)	July + La Niña (1.40x)	Mar off-season (0.88x)
38% (at threshold)	0%	$5 floor	$5 floor
30%	21%	$8.8	$5.5
20%	47%	$19.7	$12.4
5%	87%	$30 (cap)	$23

Keywords Monitored

text

coffee price, arabica price, robusta price, coffee futures, arabica futures,
KC futures, coffee above, coffee below, coffee reaches, coffee exceed,
coffee production, coffee crop, coffee harvest, coffee yield,
brazil coffee, vietnam coffee, colombia coffee, ethiopia coffee,
arabica production, robusta production, coffee bags, million bags,
coffee frost, frost event, frost damage, brazil frost,
coffee drought, coffee rainfall, cerrado, sul de minas,
coffee belt, coffee freeze, coffee, arabica, robusta, coffee market

Remix Signal Ideas

• ICE Arabica KC1 spot price: Wire real-time KC1 futures price into compute_signal — compute % distance to question threshold and compare to Polymarket probability; when the market implies a different probability than what the options surface suggests, you have a precise edge
• NOAA ENSO outlook: Automate SIMMER_ENSO_PHASE updates from the monthly NOAA CPC ENSO forecast API (free, JSON) — current hardcoded value updates only when you redeploy; automated updates capture phase transitions earlier than retail
• Brazil frost model: Pull the 10-day ECMWF or GFS 850hPa temperature forecast for Minas Gerais (lat -20, lon -45) — if anomalously cold air is forecast to reach the coffee belt within the frost window, spike conviction to 1.40x regardless of calendar month
• Vietnam rainfall index: Use CHIRPS precipitation anomaly data for Vietnam's Central Highlands during robusta flowering (Oct–Dec) — anomalous drought during flowering predicts 12–18 month forward supply shortage; fade robusta market prices that haven't incorporated this
• Brazil biennial cycle: Track whether current crop year is on-year (high) or off-year (low) in Brazil's biennial production cycle — on-years increase post-harvest supply surplus; off-years tighten; add a ±0.10x multiplier to harvest_cycle_mult accordingly

Safety & Execution Mode

The skill defaults to paper trading (venue="sim"). Real trades only with --live flag.

Scenario	Mode	Financial risk
python trader.py	Paper (sim)	None
Cron / automaton	Paper (sim)	None
python trader.py --live	Live (polymarket)	Real USDC

autostart: false and cron: null — nothing runs automatically until you configure it in Simmer UI.

Required Credentials

Variable	Required	Notes
SIMMER_API_KEY	Yes	Trading authority. Treat as high-value credential.

Tunables (Risk Parameters)

All declared as tunables in clawhub.json and adjustable from the Simmer UI.

Variable	Default	Purpose
SIMMER_MAX_POSITION	30	Max USDC per trade (reached at 100% conviction)
SIMMER_MIN_VOLUME	5000	Min market volume filter (USD)
SIMMER_MAX_SPREAD	0.08	Max bid-ask spread (8%)
SIMMER_MIN_DAYS	3	Min days until resolution
SIMMER_MAX_POSITIONS	8	Max concurrent open positions
SIMMER_YES_THRESHOLD	0.38	Buy YES if market price ≤ this value
SIMMER_NO_THRESHOLD	0.62	Buy NO if market price ≥ this value
SIMMER_MIN_TRADE	5	Floor for any trade (min USDC regardless of conviction)
SIMMER_ENSO_PHASE	neutral	ENSO climate phase: la_nina, el_nino, or neutral. Update quarterly from NOAA CPC.

Dependency

simmer-sdk by Simmer Markets (SpartanLabsXyz)

• PyPI: https://pypi.org/project/simmer-sdk/
• GitHub: https://github.com/SpartanLabsXyz/simmer-sdk