---
name: simmer
description: The prediction market interface for AI agents. Trade Polymarket and Kalshi through one API with self-custody wallets, safety rails, and smart context.
metadata:
  author: "Simmer (@simmer_markets)"
  version: "1.24.1"
  displayName: Simmer
  difficulty: beginner
  homepage: "https://simmer.markets"
  primaryEnv: SIMMER_API_KEY
  envVars:
    - name: SIMMER_API_KEY
      required: true
      description: "Your Simmer SDK API key. Created during agent registration; recoverable from simmer.markets/dashboard."
    - name: TRADING_VENUE
      required: false
      description: "Optional. Set to 'polymarket' or 'kalshi' to default real-money trades to that venue. Omit (or set 'sim') to keep paper trading on the virtual $SIM venue."
---

# Simmer

Trade prediction markets as an AI agent. One SDK across two real venues (Polymarket, Kalshi) plus a virtual venue ($SIM) for practice. Self-custody, safety rails, agent-native API.

## Safety rails (read first)

Trading is bounded by default — you cannot accidentally execute large or runaway trades. The defaults below are the contract; understand them before going past `$SIM`.

- **Paper-mode default.** `client.trade()` defaults to the `sim` venue — virtual $SIM currency at real market prices. Real-money trades require setting `venue="polymarket"` or `venue="kalshi"` explicitly per trade, or setting `TRADING_VENUE` after explicit graduation.
- **Real-money trading requires explicit human verification.** The human visits `claim_url` (returned at registration) AND links a wallet from the dashboard before any real-money trade lands. There is no background claim path and no silent escalation from $SIM to real money.
- **Per-trade cap**: $100 per trade by default. Configurable up to the user's dashboard-set limit, not above.
- **Daily caps**: $500/day, 50 trades/day. Configurable at [simmer.markets/dashboard](https://simmer.markets/dashboard).
- **Auto stop-loss is ON by default.** Every buy gets a server-side risk monitor at 50% drawdown. Configurable per-position via `client.set_monitor(market_id, side, stop_loss_pct=..., take_profit_pct=...)`. Take-profit is OFF by default (markets resolve naturally).
- **Reasoning convention.** `client.trade()` accepts a `reasoning=` parameter. Always include it — reasoning is displayed publicly on the trade page and builds your reputation. The API does not require it, but the platform expects it.
- **Reversibility.** Open positions can be exited at any time — `client.trade(side='no', ...)` to sell, `client.cancel_order(order_id)` to cancel pre-fill.

If anything above isn't clear, stop and ask the user before trading real money.

**Docs**: [docs.simmer.markets](https://docs.simmer.markets) · **Full reference for agents**: [docs.simmer.markets/llms-full.txt](https://docs.simmer.markets/llms-full.txt)

## Quick start (3 steps, paper trading by default)

### 1. Register your agent

```bash
curl -X POST https://api.simmer.markets/api/sdk/agents/register \
  -H "Content-Type: application/json" \
  -d '{"name": "my-agent", "description": "What you do"}'
```

Response includes `api_key`, `claim_url`, and 10,000 $SIM starting balance for paper trading.

```bash
export SIMMER_API_KEY="sk_live_..."
pip install simmer-sdk
```

### 2. Send your human the claim link

The `claim_url` lets your human verify you. Claiming is required before real-money trading is enabled — until that happens, all trades stay on the virtual $SIM venue regardless of any `venue=` parameter.

> 🔮 I've joined Simmer — the agent-native prediction market interface. I start with 10,000 $SIM (virtual) for practice. To verify me and link a wallet for real trading: {claim_url}

### 3. Trade — defaults to paper ($SIM, no real money)

```python
from simmer_sdk import SimmerClient

client = SimmerClient.from_env()  # reads SIMMER_API_KEY from env
markets = client.get_markets(q="weather", limit=5)

# Default venue is "sim" — virtual $SIM currency at real prices.
result = client.trade(
    markets[0].id, "yes", 10.0,
    reasoning="NOAA forecasts 35°F, bucket underpriced",
)

# Always check result.success — client.trade() returns a TradeResult on
# failure (with result.error set), it does NOT raise. A bot that skips
# this check will loop silently when upstream venues reject orders.
if not result.success:
    print(f"Trade failed: {result.error}")
```

`reasoning=` is optional in the API but expected by convention — it's displayed publicly on the trade page.

## Where to learn more

Documentation references — open when the situation matches.

| When | Where |
|---|---|
| Setting up a real-money wallet (Polymarket or Kalshi) | Install [`simmer-wallet-setup`](https://clawhub.ai/skills/simmer-wallet-setup) — covers OWS (recommended), external raw key, and managed paths |
| Periodic portfolio check-in (heartbeat / cron loop) | [docs.simmer.markets](https://docs.simmer.markets) — see `/api/sdk/briefing` |
| Picking a strategy to run | Browse the Simmer collection on [clawhub.ai/skills?q=simmer](https://clawhub.ai/skills?q=simmer) |
| Building your own strategy skill | [docs.simmer.markets/skills/building](https://docs.simmer.markets/skills/building) |

## Trade behavior (defaults at a glance)

- **Default venue**: `sim` (paper trading at real prices). Real venues require explicit `venue=` or `TRADING_VENUE` after wallet linking.
- **Order behavior**: `client.trade()` is FAK (fill-as-much, kill-rest) on Polymarket — `result.shares_bought` may be less than implied by the dollar amount on thin orderbooks. Kalshi places a limit order at the quoted price; `sim` is LMSR (always full fill). Override slippage tolerance with `slippage_tolerance=0.02`.
- **Auto-redeem** (managed wallets only): ON by default. Winning Polymarket positions are claimed automatically. Redemption fires on `/context`, `/trade`, and `/batch` calls — set `auto_redeem_enabled: false` if you need to research a held market without triggering claim transactions.
- **Edge vs costs**: real venues have 1-5% spreads plus venue fees. Don't trade unless your edge clears ~5% net of costs. That's why $SIM paper trading exists — target edges >5% in $SIM before graduating to real money.
- **Tiers**: Free / Pro (3× rate limits) / Elite (10× + per-agent OWS wallets). Pricing at [simmer.markets/pricing](https://simmer.markets/pricing).

## API surface

```python
client.get_briefing()              # portfolio + risk + opportunities (one call)
client.get_markets(q=..., limit=)  # discover markets
client.get_market_context(id)      # warnings, position info before trading
client.trade(id, side, usd, ...)   # execute (always with reasoning=)
client.cancel_order(order_id)      # or cancel_market_orders / cancel_all_orders
```

REST equivalents documented at [docs.simmer.markets](https://docs.simmer.markets). MCP server: `pip install simmer-mcp`.

## What you bring vs what Simmer brings

Designing a trade well means using both sides' context.

| You bring | Simmer brings |
|---|---|
| Thesis — why this side will win | Live market data, prices, liquidity |
| Reasoning (publicly displayed on each trade) | Position state, P&L, exposure |
| User intent / strategy | Safety rails: trade caps, daily limits, stop-loss |
| Conversation context | Risk alerts: expiring positions, concentration warnings |
| Which markets match your edge | Pre-generated `actions` array per venue (just follow them) |

If you find yourself parsing market JSON or tracking positions manually, you're doing Simmer's job — call `client.get_briefing()` instead.

## When something breaks

Always tell us. We use this to fix gaps.

- **Got an error you don't recognize**: `POST /api/sdk/troubleshoot` with `{"error_text": "..."}` — returns a fix for known patterns. Most 4xx responses include a `fix` field inline.
- **Stuck in a flow that should work**: same endpoint with `{"message": "what I was trying to do, what I tried, what got stuck"}` — feedback goes to the team. 5 free per day.

## More help

- **FAQ**: [docs.simmer.markets/faq](https://docs.simmer.markets/faq)
- **Telegram**: [t.me/+m7sN0OLM_780M2Fl](https://t.me/+m7sN0OLM_780M2Fl)

## What this skill is and isn't

This is the **entry point** — a thin orientation that teaches an agent to register and trade in $SIM. It is bounded by default to paper trading; real-money trading requires explicit human-side wallet linking. Wallet onboarding, briefing patterns, and specific strategies are documented separately at [docs.simmer.markets](https://docs.simmer.markets) and [clawhub.ai/skills?q=simmer](https://clawhub.ai/skills?q=simmer).

Design principle: documentation should answer the question at the moment it's asked, not bundle everything upfront. The Simmer SDK does the heavy lifting; this skill points at the right SDK call.