Unofficial Yahoo Finance MCP Server

An MCP server that exposes Yahoo Finance data to MCP clients (such as Claude Desktop). It runs over stdio (default, for local clients) or an HTTP transport (for standalone / containerized hosting). Market data is sourced through the yfinance library, which uses Yahoo's unofficial endpoints.

Disclaimer

• This project is not affiliated with, endorsed by, or sponsored by Yahoo. "Yahoo" and "Yahoo Finance" are trademarks of their respective owners.
• It relies on unofficial Yahoo Finance endpoints via yfinance. Those endpoints can change or break at any time, and Yahoo may rate limit or block requests. Review Yahoo's Terms of Service before use.
• Data may be delayed, incomplete, or inaccurate. Nothing here is financial advice. Do not rely on it for trading or investment decisions.
• Provided "as is", without warranty. Intended for personal and educational use. You use it at your own risk. See LICENSE.
• For commercial use, review Yahoo's Terms of Service and consider a properly licensed market-data provider instead of the unofficial endpoints.

Tools

Most get_* tools take a Yahoo Finance symbol — either a ticker (AAPL, SAP.DE) or a plain ISIN. Use search to turn a company name into one. Three tools are exceptions: get_sector and get_industry take a sector or industry key (e.g. technology, semiconductors), and get_market takes a market key (e.g. US).

Compatible clients

MCP is an open protocol, so this server is not tied to one application. Every MCP client can use it. What differs is only which transport the client speaks, and that decides how you start the server.

Locally, over stdio. The client launches the server as a subprocess and talks to it over stdin and stdout. This is the default transport and needs no network. Claude Desktop, Claude Code, Cursor, VS Code (Copilot agent mode), Zed, Windsurf, the JetBrains AI assistants, Cline, Roo Code, Continue and Goose all work this way. The configuration file differs per client, but the command is always the one shown under Quick start:

{ "command": "uvx", "args": ["benethos-yahoo-finance-mcp"] }

Over the network, streamable-HTTP. The server runs once and clients connect to http://<host>:8000/mcp. Start it with --transport streamable-http, or use the Docker image, which serves this transport by default. Browser-based and multi-user front ends need it — Open WebUI supports MCP natively over streamable-HTTP and over no other transport, because a shared web front end cannot hold one stdio process per user. LibreChat and Windsurf accept it alongside stdio.

Over the network, SSE. The older HTTP transport, still expected by some clients. Start it with --transport sse and point the client at http://<host>:8000/sse. The MCP Client Tool node in n8n connects this way.

Both HTTP transports ship without authentication of their own. Read the note under Running as a standalone server before exposing either one.

Not listed? Client support moves quickly. Check which transport yours speaks, then use the matching command above — the transports are stable even when the list of names is not.

Requirements

• uv (recommended) — manages Python, the virtual environment, and dependencies in one tool.
• Or, without uv: Python 3.11+ with pip / venv.
• git is only needed for the optional install-from-source method.

Installation

Quick start: uv + Claude Desktop

The simplest way to run the server — no clone, no manual virtual environment, no git. uvx fetches and runs it on demand from PyPI (published as benethos-yahoo-finance-mcp).

1. Install uv, if you have not already — the uv installation page covers every platform. It brings uvx, and that is the only thing needed here.

2. Add the server to claude_desktop_config.json (Claude Desktop → Settings → Developer → Edit Config):

   {
     "mcpServers": {
       "benethos-yahoo-finance-mcp": {
         "command": "uvx",
         "args": ["benethos-yahoo-finance-mcp"]
       }
     }
   }
   

   Pin a version for stability with benethos-yahoo-finance-mcp==0.5.0. To enable the optional result cache, add an env block, e.g. "env": { "YF_MCP_CACHE": "1" } (see Caching).

3. Restart Claude Desktop (quit from the tray, not just close the window). The tools then appear in the client.

Installing from source instead? You can run the unreleased main branch with uvx --from "git+https://github.com/benethos-hub/yahoo-finance-mcp.git" benethos-yahoo-finance-mcp. That path needs git on the PATH of the process the client spawns — some GUI clients don't pass a full PATH, so prefer the PyPI install above.

uvx must be on the PATH the client uses. After installing uv, fully restart the app — or use the absolute path to uvx as command. The first launch downloads the package and its dependencies, so it takes a moment. Later launches use the cache.

Other ways to install

From PyPI with pip (no uv, no clone). Install the published package into a virtual environment and run it as a module. The only platform difference is the venv interpreter path: Windows uses .venv\Scripts\python.exe, Linux/macOS use .venv/bin/python.

# Windows (PowerShell)
py -m venv .venv
.\.venv\Scripts\python.exe -m pip install benethos-yahoo-finance-mcp

# Linux / macOS (bash)
python3 -m venv .venv
.venv/bin/python -m pip install benethos-yahoo-finance-mcp

Point Claude Desktop at the absolute path of the venv interpreter and run the module (no generated console script involved):

{
  "mcpServers": {
    "benethos-yahoo-finance-mcp": {
      "command": "/abs/path/to/.venv/bin/python",
      "args": ["-m", "benethos_yahoo_finance_mcp"]
    }
  }
}

(On Windows use C:\\abs\\path\\to\\.venv\\Scripts\\python.exe as command.)

From source with uv (for development or local changes):

git clone https://github.com/benethos-hub/yahoo-finance-mcp.git
cd yahoo-finance-mcp
uv sync --extra dev          # creates .venv + installs deps from uv.lock
uv run benethos-yahoo-finance-mcp     # run over stdio

Point Claude Desktop at the checkout:

{
  "mcpServers": {
    "benethos-yahoo-finance-mcp": {
      "command": "uv",
      "args": ["run", "--project", "/abs/path/to/yahoo-finance-mcp", "benethos-yahoo-finance-mcp"]
    }
  }
}

From source with venv + pip (no uv). The only platform difference is the venv interpreter path: Windows uses .venv\Scripts\python.exe, Linux/macOS use .venv/bin/python.

# Windows (PowerShell)
py -m venv .venv
.\.venv\Scripts\python.exe -m pip install -e .

# Linux / macOS (bash)
python3 -m venv .venv
.venv/bin/python -m pip install -e .

Claude Desktop config uses the absolute path to the venv interpreter:

{
  "mcpServers": {
    "benethos-yahoo-finance-mcp": {
      "command": "/abs/path/to/.venv/bin/python",
      "args": ["-m", "benethos_yahoo_finance_mcp"]
    }
  }
}

(On Windows use C:\\abs\\path\\to\\.venv\\Scripts\\python.exe as command.)

Running as a standalone server

For use outside Claude Desktop — a network-reachable HTTP service — run an HTTP transport (streamable-http or sse). Docker is the simplest way.

Every option has both a CLI flag and an environment variable (handy for containers), with one deliberate exception noted below. Precedence is CLI > environment > default (--help lists the flags):

Logging always goes to stderr, so under stdio stdout stays reserved for the JSON-RPC protocol.

Bearer token (optional). Set YF_MCP_BEARER_TOKEN and every HTTP request must carry Authorization: Bearer <token>. Anything else gets HTTP 401. It is off by default, because the ordinary case is a server on the loopback address of the machine that uses it, where a token guards against nothing. It is a single shared secret compared in constant time, not an OAuth flow — the question is only whether the caller is expected. stdio ignores it: the client owns that process and nothing else can reach it.

A token does not make a port safe to publish. The data here is public and read-only, so the realistic damage is somebody spending your Yahoo rate limit, not reading something private. Beyond a trusted network, put a reverse proxy with real authentication in front.

Host header / DNS-rebinding guard. The MCP HTTP transport validates the Host header. A localhost bind keeps a protective allow-list (localhost/127.0.0.1). An exposed bind (0.0.0.0) accepts any Host by default, so containers and other hosts can reach it out of the box. To lock it down again, set --allowed-hosts (e.g. benethos-yahoo-finance-mcp:8000) — clients whose Host is not on the list then get HTTP 421.

Docker

The published image is the shortest path to a running server — no Python, no clone, no build. Every release is pushed to the GitHub Container Registry for linux/amd64 and linux/arm64:

docker run --rm -p 8000:8000 ghcr.io/benethos-hub/yahoo-finance-mcp:latest
# Server is now reachable at http://localhost:8000/mcp

Pin a version for anything you depend on — :0.5.0 for an exact release, :0.5 to follow its patch releases. :latest moves with every release, and :edge is built from main on demand and is not a release at all.

The image hosts the server over the streamable-HTTP transport. The stdio transport is for local subprocess use and is not what you containerize. Dependencies are installed reproducibly from uv.lock via uv.

The image is configured entirely through environment variables (see the options table above) — it carries no default command arguments, so overriding a single setting with -e does not disturb the others.

# Build it yourself instead of pulling (e.g. to run an unreleased main)
docker build -t benethos-yahoo-finance-mcp .

# Run with the built-in defaults (streamable-HTTP on 0.0.0.0:8000)
docker run --rm -p 8000:8000 benethos-yahoo-finance-mcp
# Server is now reachable at http://localhost:8000/mcp

# Override settings via -e, opt into the cache and persist it in a named volume
docker run --rm -p 9000:9000 \
    -e YF_MCP_PORT=9000 \
    -e YF_MCP_LOG_LEVEL=DEBUG \
    -e YF_MCP_CACHE=1 \
    -v benethos-yahoo-finance-mcp-cache:/cache \
    benethos-yahoo-finance-mcp

The image runs as a non-root user and includes a healthcheck on the configured HTTP port. The cache is off by default. Enable it with -e YF_MCP_CACHE=1, in which case it is written to /cache (declared as a volume) — mount a named volume there to keep it across container restarts. Pass -e YF_MCP_BEARER_TOKEN=... to require a bearer token on every request. Beyond a trusted network, front it with a reverse proxy that authenticates.

Docker Compose

A compose.yaml is provided (settings under environment:, cache in a named volume). As shipped it builds from this checkout, which is what you want while developing and the only way to run an unreleased main. To operate the released server instead, swap two commented lines at the top of the service so it pulls ghcr.io/benethos-hub/yahoo-finance-mcp — the file is then all you need, with no clone and no Dockerfile. The choice and the pull_policy values are documented in the file itself.

docker compose up -d      # build (if needed) and start in the background
docker compose logs -f    # follow logs
docker compose down       # stop and remove

This requires Docker Compose v2 (the compose CLI plugin). The server is then reachable at http://localhost:8000/mcp.

The port is published on 127.0.0.1 only, so the service is reachable from the host but not from the rest of the network. That is deliberate, since the server has no authentication of its own. To expose it, remove the 127.0.0.1: prefix from the ports: entry in compose.yaml — and put a reverse proxy with authentication in front of it.

Manual (uv or venv)

With uv (any OS):

# Streamable HTTP on http://127.0.0.1:8000/mcp
uv run benethos-yahoo-finance-mcp --transport streamable-http

# Bind all interfaces on a custom port / path
uv run benethos-yahoo-finance-mcp \
    --transport streamable-http --host 0.0.0.0 --port 9000 --path /yf

With the venv interpreter directly (Windows: .venv\Scripts\python.exe):

.venv/bin/python -m benethos_yahoo_finance_mcp --transport streamable-http

Example prompts

Once the server is connected, ask the client in plain language and it will pick the tools. Replace the bracketed placeholders with concrete values.

Price & quote

• "What's the current price of [Ticker], and how far is it from its 52-week high?"
• "Is [Ticker] trading above or below its 50- and 200-day moving averages?"
• "Get the daily closes of [Ticker] for the last 6 months and compute RSI and MACD."
• "What was the deepest drawdown of [Ticker] in the last 12 months?"
• "Compare [Ticker A] and [Ticker B] over the last 3 months and show which held up better."
• "Get current quotes for [Ticker A], [Ticker B] and [Ticker C] and compare them in a table."

Company & valuation

• "Give me P/E, beta, market cap and dividend yield for [Ticker]."
• "What does [Company name] actually do, and which sector and industry is it in?"
• "Show the last three annual income statements for [Ticker] and how revenue developed."
• "How has [Ticker]'s share count changed over the past years, and does that mean buybacks or dilution?"

Analysts & news

• "What's the analyst consensus for [Ticker], and how far is the average price target from the current price?"
• "Any upgrades or downgrades for [Ticker] in the last few weeks?"
• "What are the forward revenue and EPS estimates for [Ticker], and how were they revised recently?"
• "Summarize the recent news on [Ticker]."

Earnings & calendar

• "When does [Ticker] report next, and what EPS is expected?"
• "How did [Ticker] do against estimates in the last few quarters?"
• "When are [Ticker]'s next earnings and ex-dividend dates?"

Dividends

• "Show [Ticker]'s dividends over the last ten years and the current yield."
• "Has [Ticker] cut its dividend in the last 20 years, and did it split the stock?"

Ownership & insiders

• "Who are the largest institutional holders of [Ticker]?"
• "What share of [Ticker] is held by insiders versus institutions?"
• "Has there been notable insider buying or selling in [Ticker] recently?"

Funds & ETFs

• "What are the top holdings and sector weightings of the ETF [Ticker]?"
• "What's the asset-class split of [ETF Ticker], and which fund family runs it?"

Filings

• "Show the most recent SEC filings for [US Ticker] with links."

Options

• "Which option expiration dates are available for [US Ticker]?"
• "Show the calls and puts for [US Ticker] expiring [Date]."

Sectors & markets

• "What are the top companies and industries in the technology sector?"
• "Show the top-performing companies in the semiconductors industry."
• "Is the US market open right now, and when does it open next?"
• "How did the major indices in Europe and Asia close?"

Finding a symbol

• "Which Yahoo ticker belongs to [Company name] on [Exchange]?"
• "Resolve the ISIN [ISIN] to a Yahoo ticker."

A daily round-up

• "For [Ticker A], [Ticker B] and [Ticker C]: pull quote, six months of history, company info and analyst recommendations, then give me a short picture of each."

The server computes nothing itself. It passes through what Yahoo returns, which already includes derived figures such as moving averages, P/E, beta and dividend yield. Anything Yahoo does not carry — RSI, MACD, drawdown, sentiment, total return — the model works out from the raw series.

Symbol resolution

All get_* tools expect a Yahoo Finance symbol. Both a ticker (AAPL, SAP.DE) and a plain ISIN (US0378331005) work, since Yahoo resolves ISINs server-side. The server passes whatever it is given straight through and never rewrites it.

To turn a company name into a symbol, call search first — the same Yahoo search endpoint handles free text, tickers, and ISINs. A ticker is preferable to an ISIN in any case, because the symbol reported back then stays consistent across tools.

Two caveats. That ISINs work is observed behaviour of an unofficial endpoint, not a guarantee: it did not work in earlier versions and it may stop again. And German WKNs resolve nowhere, not through the tools and not through search — Yahoo has no lookup for them, so ask for a ticker, an ISIN or the company name instead.

Caching

An opt-in persistent cache. When enabled, successful tool results are cached in a small SQLite file with a per-tool time-to-live (TTL) to reduce load on Yahoo's endpoints and survive restarts. Fast-moving data has a short TTL, stable data a long one.

Within a single running process yfinance already reuses identical requests, so the cache mainly helps across restarts and as rate-limit protection — that is why it is off by default.

Cache names (used for --cache-ttl <NAME>=<SECONDS> and YF_MCP_CACHE_TTL_<NAME>) and their default TTLs:

• Off by default. Enable with --cache or YF_MCP_CACHE=1.
• Location: the OS user cache directory, or --cache-dir / YF_MCP_CACHE_DIR.
• Override a TTL: --cache-ttl quote=15 (repeatable) or the YF_MCP_CACHE_TTL_<NAME> env var (e.g. YF_MCP_CACHE_TTL_QUOTE=15). Set a TTL to 0 to bypass caching for that tool.

Precedence is CLI > environment > default. Errors are never cached.

When to enable it

Enable the cache (--cache / YF_MCP_CACHE=1) if you:

• run the server as a long-running or containerized HTTP service that restarts periodically (the cache survives restarts → instant repeat results).
• hit Yahoo rate limits or make many repeated identical requests over time.
• mostly query slow-changing data (search, company info, financials), where staleness is irrelevant.

Leave it off (the default) if you:

• run it locally over stdio for interactive sessions — yfinance already reuses identical requests within a single process, so the cache adds little.
• need the freshest possible data.
• use it only occasionally.

Development

Install the dev extras, then run the test, lint, and type-check steps (the same ones CI runs).

With uv (any OS):

uv sync --extra dev

uv run pytest -q                 # unit tests (offline)
uv run ruff check .              # lint
uv run ruff format .             # format
uv run mypy                      # type check
uv run pytest --cov=benethos_yahoo_finance_mcp   # coverage

With the venv interpreter directly (replace .venv/bin/python with .venv\Scripts\python.exe on Windows):

.venv/bin/python -m pip install -e ".[dev]"

.venv/bin/python -m pytest -q                 # unit tests (offline)
.venv/bin/python -m ruff check .              # lint
.venv/bin/python -m ruff format .             # format
.venv/bin/python -m mypy                      # type check
.venv/bin/python -m pytest --cov=benethos_yahoo_finance_mcp   # coverage

The unit tests mock yfinance and run fully offline. tests/smoke.py performs an ad-hoc check against live Yahoo Finance and is not part of the unit suite. CI also runs across Python 3.11–3.14 and enforces an 80% coverage floor.

Trademarks

"Yahoo" and "Yahoo Finance" are trademarks of Yahoo Inc. This project is not affiliated with, endorsed by, or sponsored by Yahoo, and it is not an official Yahoo product.

The names are used here only to describe what the software does, namely read market data from Yahoo Finance through the yfinance library. That is the only accurate way to say it. All trademarks remain the property of their respective owners.

The project itself is published as benethos-yahoo-finance-mcp and is maintained independently under the MIT licence.