Alpaca Trading & Market Data API
by Alpaca
Commission-free stock and crypto trading API. Real-time market data, trade execution, portfolio management for US equities and cryptocurrencies.
tradesmarket-datastocks+1
201 txns
1 agents
Polymarket Prediction Markets
by Polymarket Data
5.0K txns
1 agents
About
Real-time Polymarket prediction market data including trades, prices, and market activity
Categories
Access Data
For AI Agents
MCP ServerInstall the x402 MCP server to let your AI agent access this data with automatic USDC payments on Base.
Required: You need a SerenDB database to store query results.
Get your connection string from the SerenDB Console under your database settings.
Claude Desktop
Add to claude_desktop_config.json:
{
"mcpServers": {
"x402": {
"command": "npx",
"args": ["@serendb/x402-mcp-server"],
"env": {
"X402_GATEWAY_URL": "https://x402.serendb.com",
"WALLET_PRIVATE_KEY": "0x...",
"BASE_RPC_URL": "https://mainnet.base.org",
"SERENDB_CONNECTION_STRING": "postgresql://..."
}
}
}
}Claude Code
Replace 0x... with your wallet private key and postgresql://... with your SerenDB connection string.
macOS / Linux
claude mcp add x402 \ -e X402_GATEWAY_URL=https://x402.serendb.com \ -e WALLET_PRIVATE_KEY=0x... \ -e BASE_RPC_URL=https://mainnet.base.org \ -e "SERENDB_CONNECTION_STRING=postgresql://..." \ -- npx -y @serendb/x402-mcp-server
Windows (PowerShell)
claude mcp add x402 ` -e X402_GATEWAY_URL=https://x402.serendb.com ` -e WALLET_PRIVATE_KEY=0x... ` -e BASE_RPC_URL=https://mainnet.base.org ` -e "SERENDB_CONNECTION_STRING=postgresql://..." ` '--' npx -y @serendb/x402-mcp-server
Gemini CLI
Replace 0x... with your wallet private key and postgresql://... with your SerenDB connection string.
gemini mcp add x402 \ -e X402_GATEWAY_URL=https://x402.serendb.com \ -e WALLET_PRIVATE_KEY=0x... \ -e BASE_RPC_URL=https://mainnet.base.org \ -e "SERENDB_CONNECTION_STRING=postgresql://..." \ -- npx -y @serendb/x402-mcp-server
Codex CLI
Replace 0x... with your wallet private key and postgresql://... with your SerenDB connection string.
codex mcp add x402 \ --env X402_GATEWAY_URL=https://x402.serendb.com \ --env WALLET_PRIVATE_KEY=0x... \ --env BASE_RPC_URL=https://mainnet.base.org \ --env "SERENDB_CONNECTION_STRING=postgresql://..." \ -- npx -y @serendb/x402-mcp-server
Cursor
Important: Cursor has a 60s timeout. Pre-install globally first: npm install -g @serendb/x402-mcp-server
First, install globally to avoid timeout issues:
npm install -g @serendb/x402-mcp-server
Then add to ~/.cursor/mcp.json:
{
"mcpServers": {
"x402": {
"command": "x402-mcp-server",
"args": [],
"env": {
"X402_GATEWAY_URL": "https://x402.serendb.com",
"WALLET_PRIVATE_KEY": "0x...",
"BASE_RPC_URL": "https://mainnet.base.org",
"SERENDB_CONNECTION_STRING": "postgresql://..."
}
}
}
}Also works with Windsurf, Zed, and other MCP-compatible clients. See the full setup guide for details.
For Developers
Direct HTTP APIAccess data directly via HTTP using the x402 payment protocol.
How x402 Payments Work
- Send your query request to the gateway
- Receive
HTTP 402with payment requirements (amount, wallet, EIP-712 data) - Sign the payment authorization with your wallet
- Retry request with
X-PAYMENTheader containing the signature - Receive your data - payment settles automatically via USDC on Base
Step 1: Get Payment Requirements
curl -X POST https://x402.serendb.com/api/proxy \
-H "Content-Type: application/json" \
-d '{
"publisherId": "dfbf416d-3061-464c-b4b0-665692f11fd5",
"agentWallet": "0xYourWalletAddress",
"request": {
"method": "GET",
"path": "/endpoint"
}
}'This returns 402 Payment Required with the payment details you need to sign.
Step 2: Add Payment Header
After signing the EIP-712 authorization, add the base64-encoded signature:
curl -X POST https://x402.serendb.com/api/proxy \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <base64-encoded-signature>" \
-d '{ ... }'Example Prompts
Copy these prompts to use with your AI assistant. Make sure you have the x402 MCP server configured.
Analysis
Using the x402 MCP server, fetch the top 50 active prediction markets from Polymarket. Analyze the current prediction landscape: - What are the most actively traded markets right now? - Which events have the highest trading volume? - Any markets with odds that seem mispriced or surprising? - Key upcoming events that markets are focused on Save this to my SerenDB under "polymarket_active_markets" to track market sentiment over time.
Monitoring
Using the x402 MCP server, get the latest political prediction markets from Polymarket. Summarize the political forecasts: - Current odds for major political events - How have odds shifted recently? - Which races or events have the tightest margins? - Any surprising movements worth noting Save this to my SerenDB under "political_predictions" to monitor how forecasts evolve.
Research
Using the x402 MCP server, search Polymarket for markets related to crypto or technology events. Research what the crowd predicts: - Major tech/crypto events being bet on - Current probability estimates - Market liquidity and trading activity - Consensus view vs contrarian opportunities Save this to my SerenDB under "tech_crypto_predictions" for tracking industry forecasts.
Pricing
$0.0010/call
Pay per API call via x402 protocol
Publisher Details
Type: api
Added: December 6, 2025
Cache TTL: 60s
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