intoApex/tas-guard

A trading-aware safety proxy for AI agents. Put it between your AI client (Claude, ChatGPT, Cursor, your own agent) and any broker or exchange MCP server. It enforces per-order and daily limits, symbol allowlists, human approvals, a kill switch and a tamper-evident audit log, before an order ever reaches your broker.
AI client ──► TAS Guard ──► Alpaca / CCXT / any trading MCP server ──► your account
├─ blocks: over-limit orders, off-list symbols, withdrawals, leverage changes
├─ asks you: large orders, live money, "close everything"
└─ logs: every decision, hash-chained
Zero dependencies. About 2,000 lines of plain JavaScript you can read in one sitting.
New in 0.3: onchain (EVM) mode. The same limits, approvals, kill switch and audit log for agents that hold their own wallet: tas-guard rpc is a local JSON-RPC endpoint your agent uses as its RPC URL.
## Try it in 10 seconds (no broker account)
tas-guard demo runs the guard in front of a built-in paper broker with simulated prices. Add it to your AI app as an MCP server:
json
{ "mcpServers": { "tas-guard-demo": { "command": "npx", "args": ["-y", "tas-guard", "demo"] } } }
(On Windows use "command": "cmd", "args": ["/c", "npx", "-y", "tas-guard", "demo"].) Then ask your agent to buy 1 SPY at $580 (allowed), 2 SPY at $580 (held for your approval), 10 SPY (blocked: over the $2,000 per-order limit) or 1 TSLA (blocked: not on the allow list). Approve held orders with npx tas-guard approve .
## Why not a generic MCP gateway?
Generic gateways decide per tool: "createOrder is critical, require approval." They can't tell a $50 order from a $50,000 one, so you end up approving everything or nothing.
TAS Guard reads the order itself. It knows that Alpaca's placeoptionorder has a 100x contract multiplier, that ccxt's cost is a quote-currency value while amount is base units, and that ccxt answers the first live order with a preview. That's what makes "allow small orders, ask for big ones, never exceed $2,000 a day" possible.
| Broker connector | What it does on its own | With TAS Guard |
| Alpaca MCP (TAS safety score 68) | AI can place orders directly; toolsets can limit it | Per-order and daily caps, symbol allowlist, approval above a threshold |
| CCXT MCP | Has its own caps and confirm step | One policy and one audit log across every exchange you use |
| Any other trading MCP | Varies | Heuristic profile; anything unrecognized is blocked |
Safety scores and order-gating facts: tradingagentstack.com.
## Quick start (Alpaca, paper trading)
1. Write ~/tas-guard/alpaca.json (or run npx tas-guard init alpaca-mcp-server):
json
"name": "alpaca",
"profile": "alpaca-mcp-server",
"upstream": {
"command": "uvx",
"args": ["alpaca-mcp-server"],
"env": {
"ALPACAAPIKEY": "${ALPACAAPIKEY}",
"ALPACASECRETKEY": "${ALPACASECRETKEY}",
"ALPACAPAPERTRADE": "true"
},
"policy": {
"maxordervalue": 500,
"maxdailyvalue": 2000,
"approveover": 250,
"symbolsallow": ["SPY", "QQQ", "AAPL", "MSFT"]
${VAR} is read from the environment, so keys don't have to live in the file.
2. Point your MCP client at the guard instead of at Alpaca. For Claude Desktop (claudedesktopconfig.json):
json
"mcpServers": {