execution

Execute trades on prediction markets with slippage protection and order management

Quality

48%

Does it follow best practices?

Run evals on this skill

Adds up to 20 points to the overall score

View guide

Securityby

Medium

Suggest reviewing before use

Fix and improve this skill with Tessl

tessl review fix ./src/skills/bundled/execution/SKILL.md

Execution Service - Complete API Reference

Execute trades on Polymarket and Kalshi with slippage protection, maker orders, and order management.

Supported Platforms

Platform	Order Types	Features
Polymarket	Limit, Market, Maker	-0.5% maker rebate, GTC/FOK
Kalshi	Limit, Market	US regulated

Chat Commands

Place Orders

/execute buy poly <market> YES 100 @ 0.52   # Limit buy on Polymarket
/execute sell kalshi <market> NO 50 @ 0.48  # Limit sell on Kalshi
/execute market-buy poly <market> YES 100   # Market buy
/execute market-sell poly <market> NO 50    # Market sell

Maker Orders (Rebates)

/execute maker-buy poly <market> YES 100 @ 0.52   # Post-only buy
/execute maker-sell poly <market> NO 50 @ 0.48    # Post-only sell

Protected Orders (Slippage Protection)

/execute protected-buy poly <market> YES 100 --max-slippage 1%
/execute protected-sell poly <market> NO 50 --max-slippage 0.5%

Order Management

/orders open                                # View open orders
/orders open poly                           # Open orders on Polymarket
/orders cancel <order-id>                   # Cancel specific order
/orders cancel-all                          # Cancel all open orders
/orders cancel-all poly                     # Cancel all on Polymarket

Slippage Estimation

/estimate-slippage poly <market> buy 1000   # Estimate slippage for $1000 buy
/estimate-slippage kalshi <market> sell 500 # Estimate for $500 sell

TypeScript API Reference

Create Execution Service

import { createExecutionService } from 'clodds/execution';

const executor = createExecutionService({
  polymarket: {
    apiKey: process.env.POLY_API_KEY,
    apiSecret: process.env.POLY_API_SECRET,
    passphrase: process.env.POLY_API_PASSPHRASE,
    privateKey: process.env.PRIVATE_KEY,
  },
  kalshi: {
    apiKey: process.env.KALSHI_API_KEY,
    privateKey: process.env.KALSHI_PRIVATE_KEY,
  },

  // Defaults
  defaultSlippageTolerance: 0.5,  // 0.5%
  autoLogTrades: true,
});

Limit Orders

// Buy limit order
const order = await executor.buyLimit({
  platform: 'polymarket',
  marketId: 'market-123',
  side: 'YES',
  size: 100,           // $100
  price: 0.52,         // 52 cents
  timeInForce: 'GTC',  // Good-til-cancel
});

console.log(`Order placed: ${order.orderId}`);
console.log(`Status: ${order.status}`);

// Sell limit order
const sellOrder = await executor.sellLimit({
  platform: 'polymarket',
  marketId: 'market-123',
  side: 'YES',
  size: 100,
  price: 0.55,
});

Market Orders

// Market buy - executes immediately at best price
const order = await executor.marketBuy({
  platform: 'polymarket',
  marketId: 'market-123',
  side: 'YES',
  size: 100,
});

console.log(`Filled at: ${order.avgFillPrice}`);
console.log(`Filled size: ${order.filledSize}`);

// Market sell
const sellOrder = await executor.marketSell({
  platform: 'kalshi',
  marketId: 'TRUMP-WIN',
  side: 'YES',
  size: 50,
});

Maker Orders (Post-Only)

// Maker buy - only executes as maker (gets rebate)
const order = await executor.makerBuy({
  platform: 'polymarket',
  marketId: 'market-123',
  side: 'YES',
  size: 100,
  price: 0.52,
});

// Will be rejected if it would execute immediately as taker
if (order.status === 'rejected') {
  console.log('Price too aggressive - would be taker');
}

// Maker sell
const sellOrder = await executor.makerSell({
  platform: 'polymarket',
  marketId: 'market-123',
  side: 'NO',
  size: 50,
  price: 0.48,
});

Protected Orders (Slippage Protection)

// Protected buy - checks slippage before executing
const order = await executor.protectedBuy({
  platform: 'polymarket',
  marketId: 'market-123',
  side: 'YES',
  size: 100,
  maxSlippage: 0.5,  // 0.5% max slippage
});

if (order.status === 'rejected') {
  console.log(`Rejected: slippage would be ${order.estimatedSlippage}%`);
} else {
  console.log(`Executed with ${order.actualSlippage}% slippage`);
}

// Protected sell
const sellOrder = await executor.protectedSell({
  platform: 'kalshi',
  marketId: 'TRUMP-WIN',
  side: 'YES',
  size: 50,
  maxSlippage: 1,
});

Order Management

// Cancel specific order
await executor.cancelOrder('polymarket', orderId);

// Cancel all orders on platform
await executor.cancelAllOrders('polymarket');

// Cancel all orders for a market
await executor.cancelAllOrders('polymarket', { marketId: 'market-123' });

// Get open orders
const openOrders = await executor.getOpenOrders('polymarket');

for (const order of openOrders) {
  console.log(`${order.orderId}: ${order.side} ${order.size} @ ${order.price}`);
  console.log(`  Status: ${order.status}`);
  console.log(`  Filled: ${order.filledSize}/${order.size}`);
}

Slippage Estimation

// Estimate slippage before executing
const estimate = await executor.estimateSlippage({
  platform: 'polymarket',
  marketId: 'market-123',
  side: 'buy',
  size: 1000,
});

console.log(`For $1000 buy:`);
console.log(`  Avg fill price: ${estimate.avgFillPrice}`);
console.log(`  Expected slippage: ${estimate.slippagePct}%`);
console.log(`  Total filled: ${estimate.totalFilled}`);
console.log(`  Levels consumed: ${estimate.levelsConsumed}`);

Order Types

Type	Description	Best For
Limit	Execute at specific price or better	Price-sensitive orders
Market	Execute immediately at best available	Urgent execution
Maker	Post-only, gets rebate	Collecting rebates
Protected	Checks slippage before executing	Large orders

Time In Force

Value	Description
GTC	Good-til-cancel (default)
FOK	Fill-or-kill - all or nothing
IOC	Immediate-or-cancel - fill what you can

Fee Structure

Polymarket (Verified Jan 2026)

Most markets: 0% maker, 0% taker (zero fees)
15-min crypto markets: Dynamic taker fees up to ~3% at 50/50 odds; makers eligible for rebate program

Kalshi

Taker: Formula-based ~1.2% average, capped at ~2%
Maker: ~0.17% (formula-based)

Best Practices

Use maker orders when possible - Pay no fees on Polymarket (most markets)
Check slippage before large orders
Use protected orders for size > $500
Set appropriate timeInForce - GTC for patient orders, FOK for all-or-nothing
Monitor open orders - Cancel stale orders
Start small - Test with small sizes first

Repository: alsk1992/CloddsBot
Path: src/skills/bundled/execution/SKILL.md
Commit: e71a5f6

Last updated: about 12 hours ago
First committed: 6 months ago

Is this your skill?

If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.