MCP Connectors for Investing in 2026

The moving parts are simple once you name them. Your AI assistant is the host (Claude Desktop, the ChatGPT app, or a web assistant). An MCP server sits between the host and a system like your broker and exposes a set of tools the model can call: read your positions, fetch a quote, draft an order. When you ask a question, the model calls the relevant tool, gets real data back, and answers from that instead of from a stale training snapshot.

Access is the part that matters for money. The safer connectors authenticate through a regulated aggregator so your broker login never touches the tool, default to read-only, and require your explicit approval before any order is placed. If you want the plain-language version first, start with what is an MCP connector.

Picking the right kind of connector matters more than picking a favorite brand. Here is the field and what each is best for.

• Walnut. A free AI investing app with a hosted MCP connector, covering several brokers at once. From Claude or ChatGPT it reads your real holdings and gives each a keep, trim or exit read against the S&P 500; in the Walnut app it turns a thesis into a basket with target weights and places the trades you approve at E*Trade, moomoo, Public, Questrade, Stake Australia, tastytrade, Trading212, Wealthsimple, Webull Canada and Webull US, including recurring buys toward those targets. Robinhood, Schwab, Fidelity, Vanguard and Interactive Brokers connect read-only. Best for: keeping your own brokers and acting on them through one assistant.
• Interactive Brokers official connector. Certified Claude and ChatGPT connectors by June 8, 2026, opened to any MCP client on July 28, 2026. The AI reads the account and drafts orders into an “AI Instructions” area for you to submit. Best for: IBKR customers who want an assistant on a global, multi-asset account.
• Robinhood Agentic Trading MCP. Launched May 27, 2026, it lets an outside assistant trade equities, options and crypto on a Robinhood account. Best for: Robinhood customers who want an outside agent that can act there.
• Public hosted MCP. Part of the Agentic Brokerage Public launched on March 31, 2026, for Claude, ChatGPT and Perplexity, hosted by Public. Best for: Public customers who want a connector with nothing to run.
• Webull MCP and connectors. Available since August 2026 for ChatGPT, Claude and Grok, with order caps and a read-only mode. Best for: Webull traders who want limits on what an agent can do.
• tastytrade, Moomoo and TradeStation. tastytrade's self-hosted server (September 2026), Moomoo's hosted MCP, and TradeStation's MCP (January 2026, which needs a $10,000 balance and a paid Claude or ChatGPT plan). Best for: customers of those brokers.
• SnapTrade. A regulated brokerage aggregation API that connects many US brokers for reading holdings and, where the broker allows, placing trades. Best for: developers building one integration across many brokers.
• Alpaca. An API-native, commission-free brokerage with programmatic trading and a developer MCP surface. Best for: developers building their own trading agent on an API-first broker.
• Plaid. A financial-data aggregator that links bank and investment accounts for balances and holdings. Best for: pulling account and holdings data across institutions (aggregation, not trade execution).
• Finnhub. A market-data API covering quotes, company fundamentals, and news. Best for: feeding fundamentals and news into an assistant.
• Polygon. A market-data API for real-time and historical prices and aggregates. Best for: real-time and historical price feeds for an AI agent.

The table is ordered for an investor connecting their own accounts: Walnut first because it spans several brokers and acts on them with your approval, then each broker's own connector, then developer tools and data feeds, which do a different job. Schwab, Fidelity and Vanguard have no connector of their own for outside assistants that we know of (Schwab's Charley assistant lives inside Schwab's own app), so for those accounts a multi-broker connector such as Walnut, read-only, is the route. Features and availability change; verify current details on each provider's site.

Match the connector to what you are trying to do, then wire it up.

• You want to talk to your real portfolio without writing code. Use a connected assistant: Walnut connects your brokerage securely and lets you ask questions and approve trades in plain language. You can also use Walnut from your own AI client by adding its MCP server URL, https://walnutinvest.com/api/connector/mcp, as a custom connector in Claude, ChatGPT, or Codex, then signing in with a free Walnut account and approving read-only access (the connector never places trades; you approve those in the Walnut app). In Claude that is Settings, then Connectors, then Add custom connector; in ChatGPT, turn on Developer Mode (a paid plan), then Settings, then Apps, then Create app. The full per-client setup lives on the Walnut MCP connector page. Compare the wider field of connected assistants in the best AI investing app guide.
• Everything you own is at one broker with its own connector. Use that broker's official connector (Interactive Brokers, Robinhood, Public, Webull, tastytrade, Moomoo or TradeStation); it covers that broker alone.
• You are a developer building an agent. Alpaca or Interactive Brokers give you a trading API, SnapTrade gives one integration across many brokers, and Finnhub and Polygon supply the market data your agent reasons over.
• You only need account aggregation. Plaid links balances and holdings across institutions without any trading surface.
• You want to weigh specific brokerage options. Read the brokerages compared guide, then the best MCP connector for brokerages roundup.

The guides below cover the concept in depth and walk through connecting each specific broker.