entropy0 · Node.js SDK

Pre-fetch source trust for AI agents and pipelines.

npm install entropy0

Quick start

import { Entropy0Client } from "entropy0";

const client = new Entropy0Client(); // reads ENTROPY0_API_KEY from env

const result = await client.decide("https://github.com");

console.log(result.action);        // "proceed"
console.log(result.scores.trust);  // 96
console.log(result.shouldFetch);   // true

How it works

client.decide(url) calls the Entropy0 /v1/decide API and returns a DecisionResult with three axes of trust signal:

| Property | Description | |---|---| | result.action | Recommended action: proceed, proceed_with_caution, sandbox, escalate_to_human, deny | | result.scores.trust | Infrastructure identity posture (0–100) | | result.scores.threat | Abuse / threat likelihood (0–100) | | result.scores.deviation | Structural misalignment vs baseline (0–100) | | result.shouldFetch | true when action is proceed or proceed_with_caution | | result.reasonCodes | Codes explaining the decision |

Usage patterns

Gate before fetch

const result = await client.decide(url);
if (!result.shouldFetch) {
  throw new Error(`Blocked: ${result.action} — ${result.reasonCodes.join(", ")}`);
}
const response = await fetch(url);

Shadow mode (observe without blocking)

const result = await client.decide(url);
if (!result.shouldFetch) {
  console.warn("Would have blocked:", url, result.action, result.reasonCodes);
}
// proceed anyway during rollout
const response = await fetch(url);

BlockedByEntropy0Error pattern

import { Entropy0Client, BlockedByEntropy0Error } from "entropy0";

async function safeFetch(url: string) {
  const result = await client.decide(url);
  if (!result.shouldFetch) throw new BlockedByEntropy0Error(result);
  return fetch(url);
}

Error handling

import { AuthenticationError, RateLimitError, APIError } from "entropy0";

try {
  const result = await client.decide(url);
} catch (err) {
  if (err instanceof AuthenticationError) { /* bad key */ }
  if (err instanceof RateLimitError)      { /* quota exceeded */ }
  if (err instanceof APIError)            { /* err.status, err.message */ }
}

The client fails open by design — if the Entropy0 API is unreachable, catch the error and proceed rather than blocking all traffic.

Constructor options

const client = new Entropy0Client({
  apiKey:        "sk_ent0_...",    // or ENTROPY0_API_KEY env var
  defaultPolicy: "strict",         // "open" | "balanced" | "strict" | "critical"
  timeoutMs:     5000,
});

Links

• Entropy0 API docs
• Get an API key
• Python SDK
• GitHub