@paystage/mcp

PayStage umbrella MCP server: payment preflight, auth watch, and HIP-3 trade preflight.

Not financial advice. The trade preflight tool is a local policy gate only — it does not place orders or recommend trades.

Published on npm as @paystage/mcp@0.2.0.

Install

npx -y @paystage/mcp

Or:

npm install @paystage/mcp

The package exposes a stdio MCP server (bin: paystage-mcp).

MCP configuration

{
  "mcpServers": {
    "paystage": {
      "command": "npx",
      "args": ["-y", "@paystage/mcp"],
      "env": {
        "PAYSTAGE_POLICY_PATH": "./policy.json"
      }
    }
  }
}

Environment variables (all optional):

• PAYSTAGE_POLICY_PATH — path to policy.json spending rules
• PAYSTAGE_RPC_URL — Base RPC URL override

Tools

evaluate_mcp_payment — Available now

Evaluates a proposed x402 payment against a local policy file and returns a verdict before the agent signs anything.

list_outstanding_auths — Available now

Lists outstanding ERC-20, Permit2, and EIP-3009 authorizations.

evaluate_outstanding_auths — Available now

Flags outstanding authorizations that need attention (e.g. authorized but never settled).

evaluate_hip3_trade — Available now

Evaluates a proposed HIP-3 / trade.xyz order against a local TradePolicy and returns a decision: allow | review | do_not_trade.

Backed by @paystage/trade-preflight (0.1.0), which is also published on npm and can be run standalone:

npx -y @paystage/trade-preflight

The policy is passed as a tool argument; no extra environment variables are required for this tool.

Packages

Package	Version	Purpose
@paystage/mcp	0.2.0	Umbrella server (4 tools)
@paystage/auth-watch	0.1.0	Outstanding-auth tools
@paystage/trade-preflight	0.1.2	HIP-3 / trade.xyz trade preflight

Links

• Website: paystage.xyz
• HIP-3 context: docs.trade.xyz
• Source: github.com/base-buzz/paystage

License

MIT