CNN Fear & Greed Index MCP server

cnn-fear-and-greed-parse

Go package for CNN's Fear & Greed Index, a 0–100 gauge of US stock market sentiment. It returns the current score and rating, the values for the previous close, week, month and year, about a year of daily history, and the seven component indicators (market momentum, stock price strength, stock price breadth, put/call options, market volatility, junk bond demand, safe haven demand), each with its own score, rating and history of raw values. The module also ships a CLI and an MCP server, and has no dependencies outside the Go standard library.

Install

go get github.com/wildsurfer/cnn-fear-and-greed-parse/v2

Usage

package main

import (
	"context"
	"fmt"

	cnnfag "github.com/wildsurfer/cnn-fear-and-greed-parse/v2"
)

func main() {
	result, err := cnnfag.Get(context.Background())
	if err != nil {
		panic(err)
	}

	fmt.Printf("Now: %.0f (%s)\n", result.Score, result.Rating)
	fmt.Printf("One year ago: %.0f\n", result.OneYearAgo)
	fmt.Printf("History: %d daily points since %s\n",
		len(result.History), result.History[0].Date.Format("2006-01-02"))
	fmt.Printf("VIX indicator: %.0f (%s)\n",
		result.MarketVolatility.Score, result.MarketVolatility.Rating)
}

Output:

Now: 64 (greed)
One year ago: 58
History: 250 daily points since 2025-08-11
VIX indicator: 50 (neutral)

An Indicator's History holds the raw underlying series (the S&P 500 level for momentum, the VIX level for volatility, ratios and spreads for the rest), and its Score is CNN's 0–100 normalization. To use your own http.Client (timeout, proxy), replace cnnfag.HTTPClient.

CLI

For cron jobs and shell pipelines, without writing Go:

go install github.com/wildsurfer/cnn-fear-and-greed-parse/v2/cmd/cnnfag@latest

$ cnnfag
64 (greed) as of 2026-08-11T00:00:00Z
previous close 64 · week ago 60 · month ago 47 · year ago 58

$ cnnfag -json | jq .score
64.3714285714286

-json prints the full result, including the daily history. -timeout changes the request timeout (default 15s).

MCP server

cnnfag mcp runs a Model Context Protocol server over stdio, so AI assistants can query the index. It exposes one tool, getfearandgreed, with an optional includehistory argument. Configuration for MCP clients:

{
  "mcpServers": {
    "cnnfag": {
      "command": "cnnfag",
      "args": ["mcp"]
    }
  }
}

The client must be able to find the binary: use the full path (usually ~/go/bin/cnnfag) if your MCP client does not inherit your shell's PATH. Like the rest of the module, the server is built on the standard library only.

The server is also published to the MCP Registry as io.github.wildsurfer/cnnfag, with a container image at ghcr.io/wildsurfer/cnnfag for clients that prefer Docker over a local binary.

How it works

CNN does not offer a documented public API. This package requests the JSON endpoint that the Fear & Greed page itself uses:

https://production.dataviz.cnn.io/index/fearandgreed/graphdata

Shortened. The full README is on GitHub.