agent-budget-guard

Pre-payment budget check and post-payment invoice routing for AI agent x402 payments.

CommunityOnlineNo sign-inGlobalFreeCan modify data

What it can do

  • Check Budget: Check if AI agent should pay for an API call. Use before any x402 USDC or JPYC payment. Returns allow/deny with remaining budget.
  • Record Payment: Record completed x402 payment for audit log and invoice classification.
  • Classify Invoice: Classify invoice requirement for JPYC x402 micro-payment under Japan invoice system.

What data it sees

Do you need an account

No: the server works without sign-in

Pre-payment budget check and post-payment invoice routing for AI agent x402 payments. Prevents uncontrolled spending. USDC / JPYC / Japan invoice small-amount exception supported.

How to connect

How to connect agent-budget-guard to Claude

The server address to paste into Claude settings:

https://agent-budget-guard--segawa4321.run.tools

  1. Open Claude (claude.ai or the desktop app).
  2. Go to Settings → Connectors.
  3. Click Add custom connector.
  4. Paste the server address copied below into Remote MCP server URL and click Add.
  5. In a chat, click + → Connectors and switch the new connector on.

Custom connectors are available on Free, Pro, Max, Team and Enterprise plans (Free is limited to one). On Team and Enterprise an organization Owner adds the connector first under Organization settings → Connectors.

Authorization

After you click Add, a sign-in window for the service opens. Sign in with your own account and approve access. Claude never sees your password.

How to connect agent-budget-guard to ChatGPT

The server address to paste into ChatGPT settings:

https://agent-budget-guard--segawa4321.run.tools

  1. Open ChatGPT in a browser (chatgpt.com). A Plus, Pro, Business, Enterprise or Edu plan is required.
  2. Turn on developer mode once: Settings → Apps → Advanced settings → Developer mode.
  3. Open Settings → Connectors and click Create.
  4. Fill in the form: Name (anything), Description (one line about what the service does), MCP server URL (copy it below).
  5. Under Authentication choose OAuth if the service requires sign-in, otherwise None. Click Create.
  6. In a new chat open + → Apps/Connectors and enable the connector.

OpenAI has renamed this section before (Connectors → Apps/Plugins). If the label differs, search settings for "developer mode". On Business/Enterprise workspaces an admin must allow custom connectors first.

Authorization

On first use ChatGPT opens the service's sign-in window. Sign in and approve access.

How to connect agent-budget-guard to Cursor

The server address to paste into Cursor settings:

https://agent-budget-guard--segawa4321.run.tools

Fastest: click Open in Cursor below and confirm the prompt.

Manually:

  1. In Cursor open Settings → Cursor Settings → MCP and click Add new global MCP server.
  2. Paste the JSON copied below into ~/.cursor/mcp.json (per project: .cursor/mcp.json in the repo root).
  3. Save the file. The server appears in the MCP list; authorize it there if asked.

Authorization

If the service needs sign-in, an authorize button appears next to the server in the MCP list.

Server tool list (3)

Raw names from tools/list. Only developers need these.

check_budgetCheck if AI agent should pay for an API call. Use before any x402 USDC or JPYC payment. Returns allow/deny with remaining budget.
record_paymentRecord completed x402 payment for audit log and invoice classification.
classify_invoiceClassify invoice requirement for JPYC x402 micro-payment under Japan invoice system.