Best MCP Servers for Stock Market Data in 2026 (and How to Connect One to Grok or ChatGPT)
How to give Grok, ChatGPT or Claude live market data without writing code, then eleven MCP servers compared on what they expose, how fresh it is, what the free plan really allows, and whether they run on the vendor's servers or on your computer.
The best MCP server for stock market data in 2026 depends on what your AI is going to ask for. For prices and history, Massive (the company formerly called Polygon.io) and Twelve Data are the straightforward feeds. For filings and statements, Financial Datasets reads SEC filings section by section. For the widest catalogs, EODHD and Financial Modeling Prep. For what the market is saying and who is buying, that is what SentiSense is built for, and since we run it, treat that pick as ours. Below: how to connect one without code, then eleven servers that are real and reachable as of September 2026.
Connect one without code
The hosted servers work by adding a URL in your AI app's settings. Some then ask you to sign in, others to paste a key. These steps are for SentiSense, which we run and have tested with each app; other hosted servers follow the same shape with their own URL and sign-in.
Grok (grok.com): open Connectors, choose New Connector, then Custom, and paste https://app.sentisense.ai/mcp. Sign in with your SentiSense account and approve access. Grok calls anything outside its built-in catalog a custom connector, which is what you want here.
ChatGPT (chatgpt.com): turn on developer mode under Settings, then Security; that is what allows adding a connector by URL. Then open Settings, Connectors, create a connector, paste the same URL, sign in and approve. ChatGPT has renamed this area more than once; look for Plugins, Apps or Connectors.
Claude (claude.ai): open Settings, then Connectors, add a custom connector with the URL, sign in and approve.
Codex (OpenAI's coding agent, in the terminal): two commands, codex mcp add sentisense --url https://app.sentisense.ai/mcp and then codex mcp login sentisense to sign in. The full walkthrough, with what Codex can do once connected, is in our Codex guide.
Then ask about something current: "are insiders buying UBER", "what is the market mood today", "which stocks have the highest sentiment this week". A free SentiSense account covers 1,000 requests a month, with some tools returning preview depth until you upgrade.
What an MCP server changes
Until recently, giving an AI market data meant code: a script that calls an API, cleans the response and pastes it into a prompt. The Model Context Protocol turns the vendor's API into a tool the AI app can call. You add a server once, and from then on the assistant can look up a quote, a filing or a sentiment reading while it answers you.
Two things follow. The data behind the server matters more than the server, because the assistant answers with whatever it is given. And servers that run on the vendor's side and connect with a URL are far easier to adopt than ones that run on your computer, because a person who does not write code can still add a link.
The servers, compared
Official means the vendor maintains the server; it says nothing about data quality. "Hosted" means it runs on the vendor's servers and connects with a URL; "local" means it runs on your computer.
| Server | Maintained by | Best for | What it exposes | Free plan | Connect |
|---|---|---|---|---|---|
| SentiSense | Vendor | Market read, smart money, screening | Per-stock sentiment and Score, market mood, news, analyst ratings, insider, institutional and congressional data, options, earnings calendar, screener, Rating, financials, entity brief | 1,000 requests a month; some tools at preview depth | Hosted, sign in |
| Massive (formerly Polygon.io) | Vendor | Prices and history | Stocks, options, forex, crypto, futures, trades, snapshots, dividends, fundamentals, analyst ratings | 5 calls a minute, 15-minute delayed | Local, key |
| Alpha Vantage | Vendor | Broad data plus news sentiment | Prices, indicators, fundamentals, options, forex, crypto, commodities, economic data, news sentiment, earnings transcripts, congressional trades | 25 requests a day, 5 a minute | Hosted or local; Grok documented |
| Financial Datasets | Vendor | Filings and statements | Prices, statements, fundamentals, SEC filings with extracted sections, insider trades, institutional holdings, news, screening | None ongoing; $20 credit pack | Hosted, sign in; ChatGPT documented |
| Twelve Data | Vendor | Quotes and time series | Time series and quotes for stocks, forex, crypto; real-time as advertised by the vendor | 800 calls a day, 8 a minute | Hosted (cloud) or local |
| Unusual Whales | Vendor | Options flow | Options flow, dark pool, congressional trades, Greeks, volatility, fundamentals, futures | None; from $50 a month | Hosted, key |
| Finnhub | Community servers | Quotes on a budget | Real-time US quotes, fundamentals, earnings, analyst trends, news; varies by server | Finnhub's free key, 60 calls a minute | Local, key |
| Yahoo Finance | Community servers | Free, unofficial | Prices, history, company info, financials, options, news through the unofficial yfinance library | No key; no service guarantee | Local |
| Alpaca | Vendor | Brokerage data and orders | Market data, portfolio, corporate actions, order placement for stocks, ETFs, crypto, options | Real-time IEX quotes; consolidated feed delayed 15 minutes | Local, key; remote setup documented |
| EODHD | Vendor | Wide catalog | End of day, intraday and tick prices, fundamentals, news and sentiment, US options with Greeks, insider filings, macro data; 72 tools | 20 calls a day; US end of day with limited fundamentals | Hosted; key or sign in by version |
| Financial Modeling Prep | Vendor, plus a popular community build | Wide catalog | Stock data, statements, key metrics, technicals, news, SEC filings; 250+ tools in the community build | 250 calls a day | Hosted or local |
Two notes before the table gets quoted. Polygon.io rebranded to Massive in late 2025, and most directories still list the old name, so search both. Finnhub and Yahoo Finance have no official server, only competing community repos, so what you get depends on which one you install.
Where they differ
Breadth. EODHD and Financial Modeling Prep are broad generalist catalogs. Unusual Whales and Alpaca are narrow and deep on one thing each: options flow and dark pool prints for the first, brokerage data and order placement for the second. SentiSense is built around the market's read on a stock, the smart money behind it, analyst moves and a Rating, with prices as context rather than the product. Alpha Vantage and Financial Datasets also carry parts of that (news sentiment and congressional trades; insider trades and institutional holdings), so compare the rows rather than the labels.
Freshness. Real-time on a free plan is the exception. Finnhub's free key serves real-time US quotes through community servers, and Alpaca's free plan covers IEX in real time. Massive's free key is 15 minutes delayed, EODHD's free plan is end of day, and Alpha Vantage's real-time US feed starts on a paid plan. Twelve Data and Unusual Whales describe their paid feeds as real-time; treat that as the vendor's claim. Yahoo Finance community servers use the unofficial yfinance library and carry no guarantee. SentiSense serves prices delayed 15 minutes, with sentiment, ratings and filings refreshed on a schedule rather than tick by tick. Whether a delay matters depends on the question: a research question tolerates it, a trading rule does not.
Price to enter. Free plans with a real key: Massive, Alpha Vantage, Twelve Data, Finnhub, EODHD, Financial Modeling Prep and SentiSense. Verified paid entry points, as listed on each vendor's page: Finnhub from $11.99 a month, EODHD from $19.99, Twelve Data from $29, Unusual Whales from $50, Alpha Vantage's real-time US plan $99.99, Financial Datasets a $20 credit pack or a $200 subscription. SentiSense PRO is $15 a month list, or $6.75 a month with the code FALL26, which takes 55% off for as long as the subscription runs, for unlimited monthly requests at up to 300 a minute.
Hosted or local. SentiSense, Financial Datasets, Twelve Data in cloud mode, Unusual Whales and EODHD connect with a URL. Massive, the Finnhub servers and the Yahoo Finance servers run on your computer, which is fine for a developer and a real step for everyone else. Alpha Vantage and Financial Modeling Prep document both; Alpaca documents a remote setup but is a local install first.
Which one to pick
- A price and history feed for something you are building. Massive or Twelve Data.
- Filings and statements your AI can read section by section. Financial Datasets.
- The widest single catalog. EODHD or Financial Modeling Prep.
- Options flow. Unusual Whales, budget permitting.
- Placing orders from the AI. Alpaca, and read its permissions first; that is a different job from research.
- The market's read on a stock, the smart money behind it and a screener, with no install. SentiSense: add
https://app.sentisense.ai/mcpin Claude, ChatGPT or Grok, sign in, and ask.
No sign-up needed to read any of this. To try the SentiSense connector, get a free key and paste the URL above into your AI app.
Whichever you pick, put the same research question to two servers that both cover it once. The answer is only as good as the data behind the tool, and that is where the differences live.
Vendor documentation reviewed on September 15, 2026; tiers and prices change, and two vendor "real-time" claims are quoted as stated rather than measured. Educational use only, not investment advice.