# Kalshi Prediction Market

> Context and working knowledge for the Kalshi prediction-market domain. Use this skill whenever the user asks about Kalshi markets, tickers, order books, pricing, settlement, or the Kalshi API/WebSocket.

- Skill: `ratacat/kalshi-prediction-market` (Agent Skill, multi-file: 3 files)
- Install (CLI): `npx skillmds@latest add ratacat/kalshi-prediction-market`
- Raw SKILL.md: https://api.skillmd.com/api/skills/ratacat/kalshi-prediction-market/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Integrations & APIs
- Author: ratacat (https://skillmd.com/u/ratacat)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/ratacat/kalshi-prediction-market

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# Kalshi Prediction Market

**Kalshi** is a regulated prediction-market exchange. This skill provides the domain model, trading mechanics, and API conventions you need to reason about Kalshi data and to explain it clearly to users.

## Core Mental Model

1. **Binary event contracts**
   - Every tradable contract is **Yes/No** on a real‑world outcome.
   - A winning side pays **$1**, losing side pays **$0**.
   - Prices between **$0.01–$0.99** represent implied probability.

2. **Implied probability**
   - If a Yes contract trades at **$0.74**, the market implies ~**74%** chance of Yes.
   - No price is complementary (roughly **1 − Yes**, ignoring fees/spread).

3. **Fully collateralized**
   - Users pay maximum loss up‑front. No margin/leverage.
   - You can never lose more than you spend on contracts.

## Data Hierarchy

Kalshi uses a strict hierarchy:

- **Series** → template for recurring markets (shared rules/settlement).
- **Event** → specific instance within a series (a real‑world occurrence).
- **Market** → single binary contract within an event (one Yes/No outcome).

When you see “market,” clarify whether it means an **event page** (container) or a **specific market outcome** (binary leg).

## Market Objects: What Fields Mean

When interpreting Kalshi market JSON:

- **ticker**: unique identifier (string).
- **event_ticker / series_ticker**: parent identifiers.
- **title / subtitle**: human‑readable question and clarification.
- **yes_bid / yes_ask** (cents) and *_dollars*: best prices to buy/sell Yes.
- **no_bid / no_ask**: best prices to buy/sell No.
- **last_price**: last traded Yes price.
- **volume / volume_24h / open_interest**: activity and outstanding contracts.
- **open_time / close_time / expiration_time**: lifecycle timestamps.
- **status**: initialized, active/open, closed, settled.
- **result / settlement_value**: set after resolution.

## Trading Mechanics to Explain

- **Order book** on both Yes and No sides.
- **Quick/market order** crosses current spread for immediate fill.
- **Limit order** rests at a chosen price; may add liquidity.
- **Closing a position** = taking the opposite side later (sell Yes or buy No).
- **Mutually exclusive events** contain multiple markets where at most one can settle Yes.

Fees on Kalshi are **variable/quadratic**, roughly a percent of potential profit; maker orders may be discounted.

## Settlement & Resolution

- Each series defines **official settlement sources** and rules.
- Markets usually close before the strike/decision time, then settle after confirmation.
- Some markets can resolve early if `can_close_early` is true.

When asked “how does this resolve?”, reference the series rules and settlement source, then restate in plain language.

## API Conventions You Should Use

Public data (no auth needed):

- `GET /series`
- `GET /events` (events include their markets)
- `GET /markets`
- `GET /market/{ticker}`
- `GET /market/orderbook`
- `GET /market/candlesticks`
- `GET /market/trades`
- `GET /exchange/status`

Trading/account (auth required):

- `POST /orders`, `DELETE /orders/{id}`, `GET /orders/{id}`
- `POST /order-groups` and related order‑group endpoints
- `GET /portfolio/balance`, `GET /portfolio/positions`, `GET /portfolio/fills`

Auth uses an API key id plus RSA signature headers:

- `KALSHI-ACCESS-KEY`
- `KALSHI-ACCESS-TIMESTAMP`
- `KALSHI-ACCESS-SIGNATURE`

Real‑time updates arrive via **WebSocket** subscriptions to tickers.

## How to Apply This Skill When Answering

1. **Identify the exact event or market** the user means if they’re vague.
2. **Always distinguish Series/Event/Market** and restate which level you’re discussing.
3. **Convert price to probability** explicitly when helpful.
4. **Explain both sides (Yes/No) and spreads** when discussing pricing or order books.
5. **Cite rules + settlement source** for resolution questions.
6. **Stay neutral**: describe mechanics and risks; don’t give financial advice.

## Examples

- “This is a Kalshi **market ticker** — a binary contract paying $1 if Yes. At $0.62, the market implies ~62% Yes probability.”
- “The event is **mutually exclusive**, so each candidate outcome is a separate market. Exactly one can settle Yes.”
- “To get real‑time prices, subscribe to the market tickers on the Kalshi WebSocket.”

For more detail, see [reference.md](reference.md).