Stock Price API

Real-time stock quotes -- price, change %, volume, market cap, company name. All major US and intl exchanges. Pay-per-call via x402 (USDC on Base L2) -- no API key, no signup, no rate-limit wall.

Part of the klymax402 marketplace -- 100 x402 micropayment APIs for AI agents, one wallet, USDC on Base.

Quickstart -- MCP

Add to your MCP client config (Claude Desktop, Cursor, ElizaOS, etc.):

{
  "mcpServers": {
    "stock-price": {
      "url": "https://stock-price.api.klymax402.com/mcp"
    }
  }
}

Related MCP server: Stock Data MCP Server

Quickstart -- HTTP (x402)

curl -X POST "https://stock-price.api.klymax402.com/api/quote" \
  -H "Content-Type: application/json" \
  -d '{"symbol":"BTC"}'
# -> 402 Payment Required, with an x402 payment challenge in the response body

Any x402-aware client (@x402/fetch, x402-agent-tools, ATXP) handles the 402 -> sign -> retry cycle automatically.

Tools

finance_get_stock_price

Use this when you need a real-time stock price quote. Returns market data for any ticker symbol in JSON.

Parameters

Example response:

{"symbol":"AAPL","companyName":"Apple Inc.","price":198.45,"change":2.30,"changePercent":1.17,"volume":54200000,"marketCap":3050000000000,"exchange":"NASDAQ","previousClose":196.15,"dayHigh":199.10,"dayLow":196.80}

When to use: portfolio monitoring, financial analysis, building stock dashboards, price alerts, and investment research.

Not for: crypto prices (use finance_get_token_price), currency conversion (use finance_convert_currency), weather data (use data_get_weather).

Example agent prompts

• "A real-time stock price quote"

Payment

• Protocol: x402 -- HTTP-native pay-per-call, no signup, no API key

• Network: Base L2 (eip155:8453)

• Asset: USDC

• Facilitator: Coinbase CDP (primary), PayAI (fallback)

• Also reachable via ATXP (OAuth-wrapped x402, RFC 9728 protected-resource metadata)

Part of klymax402

100 x402 micropayment APIs for AI agents -- one wallet, USDC on Base, zero signup.

• Catalog: https://klymax402.com/llms.txt

• Full API reference: https://klymax402.com/llms-full.txt

• Live stats: https://klymax402.com/stats

License

MIT