Alpaca

Every fact below links to a source card; “unknown” means no source we cite confirms it.

Overview and current status

Alpaca is an API-first broker with several official agent options: hosted MCP servers behind OAuth, a local Trading MCP server you run with API keys, and a CLI.¹ The hosted Trading MCP is at https://api.alpaca.markets/mcp, with a paper-trading twin at https://paper-api.alpaca.markets/mcp.¹ Hosted access currently supports Cursor, Claude Code and Codex through plugins.¹

Agents can trade fractional equities, ETFs, crypto and multi-leg options.² Paper mode starts with $100K in simulated funds; switching to live means changing API keys.²

A separate Broker API MCP, in public beta since 2026-07-20, is for broker partners who build investing apps for their own customers.³⁴ It is not a retail path and is noted here for context.

Feature matrix

Feature	Value	Sources
Read portfolio	Yes (account, orders, positions, portfolio, market data)	1
Place orders	Yes	25
Order types	unknown
Assets	Stocks, ETFs, fractional equities, options including multi-leg, crypto	25
Paper trading	Yes, separate paper endpoint and $100K simulated balance	21
Tool filtering	ALPACA_TOOLSETS limits which tools the local server exposes	6
Limits	unknown
Notifications	unknown

Implementation details

• Hosted Trading MCP: https://api.alpaca.markets/mcp (live) and https://paper-api.alpaca.markets/mcp (paper), OAuth sign-in with an Alpaca account.¹
• Local Trading MCP v2: a full rewrite on FastMCP and OpenAPI; none of the v1 tools exist in v2.⁶ It runs over stdio with API keys and does not set up remote auth, so Alpaca warns not to expose it to the internet.⁶
• CLI: built for agents and scripts; Alpaca says it has no confirmation prompts and every command runs immediately.⁷
• Agent skills: Alpaca publishes SKILL.md files for its Trading and Broker APIs.⁸

Guardrails and risks

Guardrail	Where it is enforced	Sources
Paper endpoint and simulated balance for testing	Server side (broker)	21
ALPACA_TOOLSETS tool filtering	In the local server you run	6
Per-order approval	Not documented at the broker. The CLI has no confirmation prompts, so any approval step lives in your agent or MCP client	7
Do not expose the local server publicly	Your deployment	6

How to build against it

1. Start on the paper endpoint or a paper account.²¹
2. For hosted use, install Alpaca’s plugin in Cursor, Claude Code or Codex and sign in with OAuth.¹
3. For local use, run the v2 Trading MCP over stdio with API keys and limit tools with ALPACA_TOOLSETS.⁶
4. Add your own approval step before live orders. See Human-in-the-loop patterns.

Unknown so far

• Order types and limits for agent orders: unknown.
• Whether the hosted Trading MCP adds any broker-side confirmation: unknown.
• Agent terms of use: not yet reviewed here.

Changelog

• 2026-11-12: First version of this page.

Sources

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Suggest a correction (opens a GitHub issue)

Footnotes

1. GitHub - alpacahq/agentic: Multi-platform plugin marketplace for Alpaca APIs · GitHub. Alpaca (GitHub), official, retrieved 2026-11-12. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹

2. Alpaca - Trade with AI Using Alpaca’s MCP Server. Alpaca, official, retrieved 2026-11-12. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷

3. Alpaca Launches MCP Servers in Public Beta for Broker Partners.. Alpaca, official, retrieved 2026-11-12. ↩

4. Broker API MCP (Alpaca Docs). Alpaca Docs, official, retrieved 2026-11-12. ↩

5. Trading API MCP. Alpaca Docs, official, retrieved 2026-11-12. ↩ ↩²

6. GitHub - alpacahq/alpaca-mcp-server: Alpaca’s official MCP Server lets you trade stocks, ETFs, crypto, and options, run data analysis, and build strat. Alpaca (GitHub), official, retrieved 2026-11-12. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶

7. GitHub - alpacahq/cli: CLI for Trading API · GitHub. Alpaca (GitHub), official, retrieved 2026-11-12. ↩ ↩²

8. GitHub - alpacahq/alpaca-skills: Agent skills for Alpaca’s Trading API and Broker API: drop-in SKILL.md files for AI coding assistants · GitHub. Alpaca (GitHub), official, retrieved 2026-11-12. ↩