init() parameters

Call tp.init() once at startup, before your provider clients are imported. In practice you set three things — the key, the collector URL, and the firewall mode. Everything else has a sensible default.

import token_police as tp
import os

tp.init(
    api_key=os.environ["TOKENPOLICE_API_KEY"],
    base_url="https://collect.tokenpolice.ai",
    firewall="dry_run",   # watch first; flip to "enforce" when ready
)

import * as tp from "token-police";
import OpenAI from "openai";

tp.init({
  apiKey: process.env.TOKENPOLICE_API_KEY,
  baseUrl: "https://collect.tokenpolice.ai",
  firewall: "dry_run",
  instrumentModules: { openAI: OpenAI },   // Node: see Node & ESM
});

https://collect.tokenpolice.ai is also the built-in default in both SDKs, so you can leave base_url out. Set it anyway — an explicit URL is what makes the destination visible in your repo, and it's the one line you change to point at a self-hosted or local collector.

The firewall mode

This is the dial that decides whether TokenPolice can ever stop a call. It takes exactly three values, spelled in lower case:

A few things worth knowing:

• "off" is not "disabled". Usage is still logged for every provider, so your dashboard and cost history keep filling up. Only the check and enforcement stop.
• "dry_run" runs the whole check, including the network round-trip — that's what makes its would-block records trustworthy. Budget for up to timeout of extra latency per call (0.5 s by default), and it fails open if the collector is slow.
• The value is matched byte for byte. "Enforce" or "DRY_RUN" is not recognised: the SDK falls back to "dry_run" — never to "enforce" — so a typo can never start blocking traffic by accident. Node prints a warning; Python only prints it when log_errors=True.
• A reroute is enforcement too. A rule that swaps the model only takes effect under "enforce"; in dry-run it is recorded and nothing changes.

Python parameters

Node parameters

Same options, camelCased.

Node has no maxWorkers or tracerProvider (it's fetch-based, with no thread pool).

Environment variables

Three, and three only:

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