NestDaddy
All servers NestDaddy MCP Blog Sign inTry it free
AI and media

Spend Guard

io.github.vulinh1704/spend-guard ยท v0.2.0

Budgets, payee allowlists, price-spike checks and human approval for agents paying x402 paywalls

Website Source code Set it up

Connect Runs on your machine

Terminal
claude mcp add spend-guard -e SPEND_GUARD_POLICY=<SPEND_GUARD_POLICY> -e SPEND_GUARD_RAILS=<SPEND_GUARD_RAILS> -e SPEND_GUARD_LEDGER=<SPEND_GUARD_LEDGER> -e SPEND_GUARD_DASHBOARD_PORT=<SPEND_GUARD_DASHBOARD_PORT> -e SPEND_GUARD_APPROVAL_TIMEOUT=<SPEND_GUARD_APPROVAL_TIMEOUT> -e SPEND_GUARD_MOCK_NETWORK=<SPEND_GUARD_MOCK_NETWORK> -e ARC_PRIVATE_KEY=<ARC_PRIVATE_KEY> -e NEAR_ACCOUNT_ID=<NEAR_ACCOUNT_ID> -e NEAR_PRIVATE_KEY=<NEAR_PRIVATE_KEY> -- npx -y @vulinh1704/[email protected]
claude_desktop_config.json
{
  "mcpServers": {
    "spend-guard": {
      "command": "npx",
      "args": [
        "-y",
        "@vulinh1704/[email protected]"
      ],
      "env": {
        "SPEND_GUARD_POLICY": "<SPEND_GUARD_POLICY>",
        "SPEND_GUARD_RAILS": "<SPEND_GUARD_RAILS>",
        "SPEND_GUARD_LEDGER": "<SPEND_GUARD_LEDGER>",
        "SPEND_GUARD_DASHBOARD_PORT": "<SPEND_GUARD_DASHBOARD_PORT>",
        "SPEND_GUARD_APPROVAL_TIMEOUT": "<SPEND_GUARD_APPROVAL_TIMEOUT>",
        "SPEND_GUARD_MOCK_NETWORK": "<SPEND_GUARD_MOCK_NETWORK>",
        "ARC_PRIVATE_KEY": "<ARC_PRIVATE_KEY>",
        "NEAR_ACCOUNT_ID": "<NEAR_ACCOUNT_ID>",
        "NEAR_PRIVATE_KEY": "<NEAR_PRIVATE_KEY>"
      }
    }
  }
}
~/.cursor/mcp.json
{
  "mcpServers": {
    "spend-guard": {
      "command": "npx",
      "args": [
        "-y",
        "@vulinh1704/[email protected]"
      ],
      "env": {
        "SPEND_GUARD_POLICY": "<SPEND_GUARD_POLICY>",
        "SPEND_GUARD_RAILS": "<SPEND_GUARD_RAILS>",
        "SPEND_GUARD_LEDGER": "<SPEND_GUARD_LEDGER>",
        "SPEND_GUARD_DASHBOARD_PORT": "<SPEND_GUARD_DASHBOARD_PORT>",
        "SPEND_GUARD_APPROVAL_TIMEOUT": "<SPEND_GUARD_APPROVAL_TIMEOUT>",
        "SPEND_GUARD_MOCK_NETWORK": "<SPEND_GUARD_MOCK_NETWORK>",
        "ARC_PRIVATE_KEY": "<ARC_PRIVATE_KEY>",
        "NEAR_ACCOUNT_ID": "<NEAR_ACCOUNT_ID>",
        "NEAR_PRIVATE_KEY": "<NEAR_PRIVATE_KEY>"
      }
    }
  }
}
.vscode/mcp.json
{
  "servers": {
    "spend-guard": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@vulinh1704/[email protected]"
      ],
      "env": {
        "SPEND_GUARD_POLICY": "<SPEND_GUARD_POLICY>",
        "SPEND_GUARD_RAILS": "<SPEND_GUARD_RAILS>",
        "SPEND_GUARD_LEDGER": "<SPEND_GUARD_LEDGER>",
        "SPEND_GUARD_DASHBOARD_PORT": "<SPEND_GUARD_DASHBOARD_PORT>",
        "SPEND_GUARD_APPROVAL_TIMEOUT": "<SPEND_GUARD_APPROVAL_TIMEOUT>",
        "SPEND_GUARD_MOCK_NETWORK": "<SPEND_GUARD_MOCK_NETWORK>",
        "ARC_PRIVATE_KEY": "<ARC_PRIVATE_KEY>",
        "NEAR_ACCOUNT_ID": "<NEAR_ACCOUNT_ID>",
        "NEAR_PRIVATE_KEY": "<NEAR_PRIVATE_KEY>"
      }
    }
  }
}

Replace the values in angle brackets with your own. Keys stay on your machine; we never see them.

Tools

This server runs locally, so its tools are listed by your MCP client once it starts.

Environment variables

NameDescription
SPEND_GUARD_POLICY
Optional		Policy JSON file: networks, budgets, approval amount, spike ratio, known services and their payees. Without one, every payment waits for your approval.
SPEND_GUARD_RAILS
Optional		How to pay: mock (pays nothing), near, arc, gateway, or a comma list. arc and gateway need ARC_PRIVATE_KEY, near needs NEAR_ACCOUNT_ID and NEAR_PRIVATE_KEY.
SPEND_GUARD_LEDGER
Optional		Decisions file, read back on start so a restart keeps today's spend; servers on one file share one budget. Default ~/.spend-guard/ledger.jsonl; off keeps it in memory.
SPEND_GUARD_DASHBOARD_PORT
Optional		Port of the approval dashboard on 127.0.0.1. 0 picks a free one; off means no dashboard, and payments that need approval are declined.
SPEND_GUARD_APPROVAL_TIMEOUT
Optional		Seconds a payment waits for your answer before it is declined. Raise it together with your client's tool timeout.
SPEND_GUARD_MOCK_NETWORK
Optional		Network the mock rail pretends to pay on.
ARC_PRIVATE_KEY
Optional, secret		Agent key for the arc and gateway rails. Testnet keys only.
NEAR_ACCOUNT_ID
Optional		Agent account for the near rail (testnet).
NEAR_PRIVATE_KEY
Optional, secret		Agent key for the near rail. Testnet keys only.

Details

Package@vulinh1704/[email protected] (NPM, stdio)
First published31 Oct 2026
Last updated31 Oct 2026
Registry nameio.github.vulinh1704/spend-guard

More ai and media servers See all

  • bv7x strategy agents

    Find bv7x prediction agents on Robinhood Chain by market; quote their sealed calls, sold via x402.

  • Chronary

    Calendar API for AI agents: events, availability, Google/Microsoft setup, scheduling, and iCal.

  • Mastering

    Audio mastering for AI agents: LUFS analysis, Suno artifact cleanup, free daily master.

  • Modulos AI Governance Platform

    Evaluate Modulos (EU AI Act, ISO 42001, NIST AI RMF): capabilities, trust, comparisons. Book a demo.

  • naulon

    Check citations and retractions by DOI, and see the x402 price an AI agent pays to cite a source.

  • NextConstraint

    Your SaaS funnel's costliest leak, its fix, watchdog alerts and verdicts, from NextConstraint.

Listing data from the official MCP registry. Status and tools from NestDaddy's daily check. Browse all MCP servers.