spend-cap

stop runaway AI agent costs before they happen.

spend-cap patches Node.js fetch to intercept all AI API calls (OpenAI, Anthropic, Gemini) and enforce a hard daily spending limit. when the cap is hit, requests are blocked — no $800 surprise bills.

how it works

one line to add to any Node.js app:

SPEND_CAP=5 node --import @safetnsr/spend-cap/register app.js

tracks spend in a local state file. resets daily. zero dependencies. no cloud required.

why

Google Gemini has no spending limit. OpenAI billing alerts are email-only. Anthropic rate limits are server-side. none of these stop a runaway agent loop at 3am.

spend-cap is the client-side kill switch.

pair with

• vet — audit your AI coding workflow before and after sessions
• pinch — track cumulative AI costs over time