License Compare

{
  "a": {
    "family": "permissive",
    "id": "MIT",
    "title": "MIT License"
  },
  "asOf": "2026-10-11T14:39:34.651Z",
  "attribution": "License list: SPDX (CC0-1.0). Summaries: Choose a License (choosealicense.com, CC BY 3.0).",
  "b": {
    "family": "strong-copyleft",
    "id": "GPL-3.0",
    "title": "GNU General Public License v3.0"
  },
  "conditions": {
    "onlyA": [],
    "onlyB": [
      "State changes",
      "Disclose source",
      "…1 more"
    ],
    "shared": [
      "License and copyright notice"
    ]
  },
  "degraded": false,
  "disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
  "limitations": {
    "onlyA": [],
    "onlyB": [],
    "shared": [
      "Liability",
      "Warranty"
    ]
  },
  "notChecked": [
    "whether the two licenses can be combined in one project: compatibility is a legal question this does not answer",
    "license text, exceptions and jurisdiction-specific effects",
    "…1 more"
  ],
  "permissions": {
    "onlyA": [],
    "onlyB": [
      "Patent use"
    ],
    "shared": [
      "Commercial use",
      "Modification",
      "…2 more"
    ]
  },
  "reasons": [
    "License list: SPDX (CC0-1.0). Summaries: Choose a License (choosealicense.com, CC BY 3.0).",
    "Family ranks: public-domain-like, permissive, weak copyleft, strong copyleft, network copyleft.",
    "…1 more"
  ],
  "source": "computed locally",
  "stricter": "GPL-3.0",
  "summary": "MIT (permissive) vs GPL-3.0 (strong-copyleft): GPL-3.0 is stricter. Duties only in MIT: none; only in GPL-3.0: State changes, Disclose source, Same license.",
  "verdict": "DIFFERENT_FAMILY"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://license-intel.x402tookit.com/license-compare?a=MIT&b=GPL-3.0'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - 'https://license-intel.x402tookit.com/license-compare?a=MIT&b=GPL-3.0' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

// Pays at most $0.02 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.02" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.02 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Flicense-intel.x402tookit.com%2Flicense-compare
const res = await pay("https://license-intel.x402tookit.com/license-compare?a=MIT&b=GPL-3.0");
console.log(res.status, await res.text());

# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.02 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.02"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://license-intel.x402tookit.com/license-compare?a=MIT&b=GPL-3.0")
    print(res.status_code, res.text)