Spend Brake runs on your own machine — the client starts it, so there is no endpoint to ping. Last commit 10 Nov 2026.
Capped search, maps and other paid APIs over MCP, with hard dollar limits per key.
What the code does
We read the source, 1 d ago · rules 995398eba69f
Found in continuous integration, deployment or infrastructure files, or in a neighbouring package of the same monorepo. None of this is installed when you add the server: it describes how the project is built and released. We list it because a leaked key in a build pipeline is still a real problem, but it is not something this server does on your machine.
const child = io.spawn(bin!, args, { stdio: 'inherit', env });
return client.eval(s.source, keys.length, ...keys, ...args);
Is this your server and something here is wrong? Tell us — corrections are free and do not require a plan.
Nothing serious here today
Today is the operative word: we check Spend Brake every 15 minutes and re-read its code on every release. Watch it and you find out the day that stops being true.
Connect this server
This server runs on your own machine — install it with the package manager and the client starts it for you. Package name taken from the official registry entry.
claude mcp add spend-brake -e 'BRAKE_KEY=<BRAKE_KEY>' -e 'BRAKE_URL=<BRAKE_URL>' -e 'BRAKE_API_URL=<BRAKE_API_URL>' -- npx -y @spend-brake/mcp{
"mcpServers": {
"spend-brake": {
"command": "npx",
"args": [
"-y",
"@spend-brake/mcp"
],
"env": {
"BRAKE_API_URL": "<BRAKE_API_URL>",
"BRAKE_KEY": "<BRAKE_KEY>",
"BRAKE_URL": "<BRAKE_URL>"
}
}
}
}[mcp_servers.spend-brake]
command = "npx"
args = ["-y", "@spend-brake/mcp"]
env = { BRAKE_KEY = "<BRAKE_KEY>", BRAKE_URL = "<BRAKE_URL>", BRAKE_API_URL = "<BRAKE_API_URL>" }{
"mcpServers": {
"spend-brake": {
"command": "npx",
"args": [
"-y",
"@spend-brake/mcp"
],
"env": {
"BRAKE_API_URL": "<BRAKE_API_URL>",
"BRAKE_KEY": "<BRAKE_KEY>",
"BRAKE_URL": "<BRAKE_URL>"
}
}
}
}{
"servers": {
"spend-brake": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"@spend-brake/mcp"
],
"env": {
"BRAKE_API_URL": "<BRAKE_API_URL>",
"BRAKE_KEY": "<BRAKE_KEY>",
"BRAKE_URL": "<BRAKE_URL>"
}
}
}
}Put your own values in place of
<BRAKE_KEY> (A Spend Brake virtual key (sb_live_…); its caps apply to every call), <BRAKE_URL> (The Spend Brake proxy, e.g. https://proxy.spendbrake.dev), <BRAKE_API_URL> (The Spend Brake admin API, for the budget tool and for --admin, e.g. https://app.spendbrake.dev).
The author’s registry entry marks them as required.
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Spend Brake — questions
Answers built from our own checks of this server.