Yahoo Finance MCP Server

Live company data and news inside Claude, by ticker. Python + official MCP SDK (FastMCP, stdio) + yfinance.

Building a new MCP server for a different site? Start from MCP_PLAYBOOK.md — a self-contained recipe (with the common failure modes) that uses this repo as the reference implementation.

Tools

Non-US listings need the exchange suffix: D05.SI (SGX), 0700.HK (HKEX), 7203.T (Tokyo).

Related MCP server: Yahoo Finance MCP Server

Install

cd "D:\Documents\AI Automation\Claude Code Projects\Yahoo Finance"
python -m venv .venv
.venv\Scripts\pip install -r requirements.txt

(Already done — the venv in this folder is ready.)

Register in Claude Desktop

Add to %APPDATA%\Claude\claude_desktop_config.json, then restart Claude Desktop:

{
  "mcpServers": {
    "yahoo-finance": {
      "command": "D:\\Documents\\AI Automation\\Claude Code Projects\\Yahoo Finance\\.venv\\Scripts\\python.exe",
      "args": ["D:\\Documents\\AI Automation\\Claude Code Projects\\Yahoo Finance\\server.py"]
    }
  }
}

Register in Claude Code

claude mcp add yahoo-finance -s user -- "D:\Documents\AI Automation\Claude Code Projects\Yahoo Finance\.venv\Scripts\python.exe" "D:\Documents\AI Automation\Claude Code Projects\Yahoo Finance\server.py"

-s user makes it available in every project.

Register in Claude chat (claude.ai) — custom connector

claude.ai only accepts remote servers, so the server must be hosted at a public HTTPS URL. The same server.py serves this with the --http flag (Streamable HTTP at /mcp).

Deploy free on Render (~10 min, one time):

1. Push this folder to a GitHub repo (.venv is gitignored).

2. At https://render.com → New → Web Service → connect the repo. render.yaml is picked up automatically (build: pip install -r requirements.txt, start: python server.py --http, free plan).

3. Copy the service URL, e.g. https://yahoo-finance-mcp.onrender.com.

Then in any Claude account: Settings → Connectors → Add custom connector → paste https://<your-service>.onrender.com/mcp → Add (no authentication needed).

Notes:

• Render's free tier sleeps after ~15 min idle; the first tool call after a pause takes ~30–60 s to cold-start, then it's fast.

• The endpoint has no auth — anyone with the URL can query it. It only serves public market data, but don't post the URL anywhere.

• If tool calls fail from the cloud but work locally, Yahoo is rate-limiting the host's IP — redeploy or upgrade the instance.

Run manually (debugging)

.venv\Scripts\python.exe server.py          # stdio (Claude Desktop / Code)
.venv\Scripts\python.exe server.py --http   # Streamable HTTP on :8000/mcp (claude.ai)

Speaks MCP over stdin/stdout; logs go to stderr. Data is unofficial Yahoo Finance via yfinance — fine for screens and sanity checks, not a substitute for filings or CapIQ on anything that goes in a deliverable.